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Alfa 164 Automatic Transmission Repair 16-01

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#1 · (Edited)
AR164 Alfa 164 Automatic Transmission Repair 16-01

Here is text of my tech article from Feb 2006 Alfa Owner. If you have copy of that issue there are some pictures I sent along with article:

Oct 2010 I added pictures to this first post and then to post 9 similiar to ones I used in original Alfa Owner article

Also I did governor seal change and that is now on page 2 at post 54 and post 64 of this thread with pictures

Alfa 164 Automatic Transmission Repair 16-01
Replacing bad spring in Accumulator A to cure slow/harsh gear engagement.
By Alfisto Steve AROC 164 Tech Advisor

Well, if you have a 1991-1993 Alfa 164 with a ZF 4HP18Q AUTOMATIC and it works well it is a smooth shifter, but things can go wrong. This article will cover a few and what I and others have found to be possible repair solutions.

I have been a 5-speed fan with my 91 164 base model I have owned since new so I have been late getting into automatic world but I had to help a friend out with his 95LS a couple years ago. Now that model uses a computer controlled version of the ZF, the 4HP18E. More on that model possibly in a later article as tech data hard to find and understand, I now also own a 91 164B with AT that I had to correct a shifting problem listed below.

Anyhow as I had to understand something about my friend’s 95, and also repair a 91 164L automatic unit I had in my spares, I searched the internet and found Eriksson Industries division of Wentworth Engineering, 146 B Elm Street, Old Saybrook, CT. 06475, 800-388-4418 at Eriksson Industries Usually when I call or email I get Nat Wentworth himself to answer. He is a treasure trove of information and their web site has a three (3) page exploded view of transmission with index numbers. He is very helpful and he suggested I buy a copy of the Saab 9000 service manual Saab order number 361097 on this transmission. He had a new copy of manual in stock. The outer case on Saab ZF transmission is somewhat different but the parts inside are pretty much the same as a 91-93 164 transmission. This Saab shop manual has very good troubleshooting, disassembly, assembly and testing procedures. So armed with this Saab manual, the website with exploded parts views like this 4HP18Q DIAGRAMS and Alfa 164 shop manual section 16 on automatic I tackled the ZF automatic.

The easiest to fix and most common ailments I have come across are these problems:
Transmission slow to go into drive from Park or Reverse and slow 4-3 downshifts. Cause - weak Accumulator A spring.
Transmission with a hard slamming clunk into drive or harsh 4-3 downshifts. Cause - broken Accumulator A spring.

Link to picture of broken spring from Fred: http://www.alfabb.com/bb/forums/164...164-168-1991-1995/166746-delayed-shift-into-drive-4-3-downshift-reason-pic.html

These problems are caused by a $4 spring in Accumulator A which is attached to bottom of valve body (distribution box) in top of transmission. If spring just weak and slightly compressed shifting will be slow but if spring cracked shifting will be slow and engine can race and then you can get that harsh slamming into gear.

Other problems such as erratic shifting/downshifting can be repaired too according to AROC member Lorinda Pate and verified by Mr. Wentworth. So here I quote Nat in his email reply:
“The problem with governor seals breaking is quite common in the
Alfa and Saab 4HP18Q transmission.

Common symptoms: 1. shifting up too soon, or not down shifting
when slowing down. Can shudder or attempt to stall engine when
stopping. 2. Occasionally no reverse engagement. 3. Shifting up and down seemingly at random, while driving at steady speed.


There are three seal rings on the back side of the governor
housing, a metal ring and two rubber rings, the main oil
pressure is supplied to the governor between the metal ring and
the center ring. Regulated governor pressure is supplied to
the valve body between the two rubber rings. When the center
ring breaks there will be cross leakage into the governor
passage and the valve body will interpret this increased
pressure as increased speed, thus shifting too soon or not down
shifting at the correct time. There is a valve which blocks
reverse application when governor pressure is above a certain
point, thus preventing reverse engagement.

There is a spring in the valve body which occasionally breaks,
that will cause harsh engagement into D, and/or a harsh
downshift from 4 to 3. This spring fits into the small housing
on the bottom of the valve body opposite the throttle valve
valve with roller on end).
Nat
Eriksson Industries
1-800-388-4418
Eriksson Industries “

I have not experienced the governor seal problem so have not yet attempted that repair. However, Lorinda Pate has had it done and she submitted a write up about it which has prompted this first article to be written about the spring replacement. Look for another article soon on his repair story on governor seals, but first I will just cover how to change that pesky $4.50 spring for that slow/harsh N-D and 4-3 shifting. I know of 4 to 6 of us who have now fixed our shifting woes by just changing the spring Nat addresses in last his paragraph.

Changing Accumulator A rear spring.

There are two springs in Accumulator A, but Nat says smaller front one never a problem and ZF doesn’t even stock it. If you look in exploded view page 3 on web site 4HP18Q DIAGRAMS you will see spring that goes bad near top of view the spring is index 26.390 (ZF part number 0732-042-227). That is the spring to change, but since I am already going in accumulator housing I also ordered Accumulator D spring index 26.420 (ZF part number 0732-042-197 for about $7.50). Why not have new spring just in case. Suggestion: Print off page 3 from web site.

How to get to valve body
Reference: 1991-93 AR164 shop manual section 16-35/36

1. Set parking brake and put gear selector in low (position 1).
2. Open hood, remove air flow meter/air cleaner box top and bottom, disconnect cruise control actuator and ABS line clamps from lower air cleaner mounting bracket and tie out of way. Remove mounting bracket and lift coolant tank return hose up and tie up with a bungee cord.
3. Using a 1/4:” drive ratchet, extension and 10mm socket locate and remove 4 corner bolts and hold down clamps that secure steel cover to top of transmission and one bolt holding front bracket to cover for thermostatic valve.
4. Carefully remove cover and rubber gasket (reuse gasket).
5. Using a Torx 27 serrated bit in a correct bit socket holder locate and loosen 10 larger headed Torx head bolts around perimeter of valve body. Note: there are 8 long bolts, one a little shorter in left front corner nearest engine and one even shorter one right front corner nearest headlight. Do not mix up. Leave them in valve body once loosened. Caution: If using regular socket to hold bit glue and tape bit securely in socket as you do not want to drop it into transmission.

Now to work on valve body and change Accumulator Spring
References: Saab 9000 AT shop manual page 286 and 164 shop manual pg 16-36

6. Once 10 bolts loose, carefully lift valve body straight up off transmission and put it on a very clean work bench covered with lint free shop towels inside a clean tray if possible.
7. Now go back to transmission and check that gear shifting bell crank did not lift up. Refer 164 manual see section 16-38.
8. Now to change Accumulator Spring you will need to remove those loose ten (10) Torx 27 bolts and carefully mark remember where two shorter ones go or hold them in place with a square piece of clean stiff material as you turn valve body upside down.
9. Before you remove end cover index 26.440 notice Accumulator A has a small spring loaded passing gear plunger with roller on it sticking out other end. Be sure it is spring loaded and moves against spring. How springy depends on condition of infamous rear spring inside. There are two springs as I mentioned earlier for this plunger. One index 26.340 nearest to roller end not the bad one.
10. Also note that gear selector index 26.376 is next to it in Accumulator D position. THIS PLUNGER must be fully retracted in low gear (position 1) when reinstalling valve body on transmission.
11. With body upside down locate accumulator body end cap index 26.430 and four screws holding it on. Loosen one on Accumulator D end slightly and remove other three.
12. Slowly pivot end cap open on remaining screw as poppet/spring can fly out.
13. Remove poppet/plunger index 26.400/26.396 and then infamous bad boy spring 26.390 (ZF 0732-042-227) in one or two pieces if broken.
14. Replace spring with new one and reinstall poppet correctly.
15. Now rotate cover some more and remove poppet index 26.410 and spring index 26.420. Compare spring height to new spring 0732-042-197, replace if shorter.
16. Reinstall poppet, and while pushing in both poppet/springs assemblies close cover install screws and torque to 6Nm (4 lb ft).
17. Check roller plunger for spring tension and push shifter plunger all the way into valve body.
18. Turn valve body back over and be sure ten bolts in proper positions as defined in Step 5.
19. Ensure shifter plunger still fully retracted in valve body and gear selector in car still in position 1.
20. Set valve body back on transmission engaging gear selector into selector bell crank. Tighten 10 Torx bolts to 10 Nm (5.8 ft lb).
21. Reinstall top cover and gasket, fixing clamps and 5 bolts, torque lightly to 6 Nm (4.4 ft lb).
22. Reinstall air flow meter/air cleaner top temporarily, hook up electrical connector to air flow meter and put car in park.
23. Start up and check that gear selector engaged in shifter linkage. If transmission will engage into Drive, Neutral, Reverse properly, finish reinstalling air cleaner and cruise control parts and take a test drive.
24. If transmission will not engage gears shifting plunger did not engage in shifter bell crank and you will have to remove valve body and set up plunger and shifter again to position 1 and plunger fully retracted.

If you have governor seal problems as described by Nat or Lorinda Pate refer to Alfa 164 shop manual section 16 pages 39-41 steps 1 through 17 and/or appropriate sections of Saab manual and order parts and repair info as needed from Eriksson Industries.

Here is Lorinda’s email:

> From: Lorinda Pate <lorindy@pacbell.net>
> Date: Thu Nov 3, 2005 11:24:52 PM America/Los_Angeles
> To: editor@aroc-usa.org
> Subject: Alfa 164 bulletin for inclusion in your publication
>
> Dear Editor,
> I hope you will find this item to be of interest to owners and repair
> facilities who deal with Alfa 164s. Please include it in your Alfa
> Romeo publications and websites.
>
>
> Read This Before You Rebuild or Replace Your 4HP-18 ZF Automatic
> Transmission:
> If your 164's automatic transmission exhibits all or some of the
> following symptoms, there may be an inexpensive alternative to
> removal/rebuild/replacement of the unit. This simple repair eliminated
> a problem that several shops thought could only be solved by a > rebuild.
>
> Here is what was done:
> Replaced 3 seal rings on the governor housing, and replaced an
> accumulator valve spring in the valve body that was cracked. Flushed
> all the ATF from the system, replaced it with Dextron III and added
> Red Lube Guard. All of this took approximately 8 hours, and total cost
> was $667.92.
>
> Symptoms:
>
> 1) Changes up early and haphazardly, sometimes changing down almost
> immediately.
>
> 2) Sometimes won't go into reverse without shifting through all the
> gears "1", up to "park" and back down several times.
>
> 3) Overdrive shifts in and out early. At idle, car sometimes shudders
> and surges. It works fine when shifted manually.
>
> 4) (This developed later, and led me to call ZF for a new tranny.)
> When shifting into a forward gear, or reverse, from "park", a clunk is
> heard. Also, when the car downshifts from overdrive into the lower
> gear, again, a clunk.
>
> Who to call:
>
> I called Nat Wentworth at Erickson Industries (800-388-4418), the ZF
> Distributor in Connecticut, as referred from the ZF Headquarters
> (847-478-6868 x6761) in Illinois.
> My intent was to purchase a factory-refurbished 4HP-18 ZF transmission
> to replace mine.
>
> Nat asked what my symptoms were, and told me that with about $100
> worth of parts and a good transmission shop, the problems could be
> repaired without removing the unit from the car. Nat sent the parts,
> gave detailed verbal instructions and faxed tech sheets to Rusty at
> Alliance Transmissions in San Marcos, CA.
> (Do-it-yourselfers, please don't call Rusty for advice, call Nat or
> his staff.)
>
> This repair solved a problem that had been ongoing since the car was 3
> years old. The previous owner drove it sparingly, shifting
> manually, and changed the ATF every 20K miles. My 164L now has 106K
> miles on the odometer and the gear changes are imperceptible. What a
> fun car to drive! Absolutely amazing difference!!
>
> If you are having similar problems, first call Nat at Erickson, then
> find yourself an honest transmission shop that isn't adverse to taking
> advice. Even Alliance didn't believe this would solve the problem
> until Nat talked to them, and several mechanics treated me like I was
> certifiably insane for insisting on finding an alternative to a
> rebuild. Nat is a Godsend!
>
> Lorinda Pate, Carlsbad, CA
> November 2, 2005
 

Attachments

#3 ·
To change fluid and check filter you need to remove filter cover plate underneath tranny. It is round cover with 3 10mm hex bolts and has a magnet inside it so don't loose magnet in catch pan.

Once fluid drains out you can pull round plastic mesh filter element out with a pair of pliers and check it for cleanliness.

Cover has o-ring as does filter element both are reuseable but if you feel like using new ones get a filter kit from Saab dealer for Saab 9000 w/AT or order kit from IAP or from http://www.erikssonindustries.com/
 
#4 ·
If they're reusable, that's fine with me. I assume that checking this on a 16 year old car is good idea, or is it okay to just replace the fluid.

Also, is there a different recommended type of tranny fluid used in in these geatboxes beyond what's stated in the owner's manual? I have seen synthetic automatic transmission fluid used in the 5-speed MTX for my SHO, so this why I ask the question.
 
#7 · (Edited)
164 ATX filter

Here is shot from shop manual pg 16-28 Note: There is supposed to be a small rectangle magnet laying in AL filter cover. Look for it in your oil drain pan if it is missing from cover.
 

Attachments

#8 ·
Alfa 164 Automatic Trasmission Repair 16.01

Steve, you great man. Your advice re. 164 automatic trasmission is what I needed - perfect - ... You mention an article from Feb 2006 Alfa Owner with some pictures. How can I have copy of these pictures? I live in Australia and I can't have access to the magazine. I will repair the trasmission myself following your directions, but, I am sure, the pictures will help. Thankyou again for your help. Enzo. Alfetta '80 (the best) - Alfa 6 (only one in Australia) - GTV6 GP 86 - 164L '92:)
 
#9 · (Edited)
Not sure your second gear problem the same as what we covered in article. do you have similiar symptoms?

As for more lost pictures I found them on my old computer.

I suggest you email Nat Wentworth at eriksson.indust@snet.net with your tranny's problem and let him advise you. His web site Eriksson Industries

As for changing Accumulators D and A springs Accumulator D one on left and usually not bad but I check it against new spring and shange is height is different anyway. Part number is 0732-042-197 for D spring (index 26.420 in parts breakdown).

Now Acumulator A spring 0732-042-227 (index 26.390) is the one on the right is usually either broken or collapsed and causes slow P to D engagment and slow or harsh 4-3 downshifts. There are two springs inside but small front 0732-041-643 (index 26.350) one for passing gear roller shaft on other end of accumulater A body does not seem to go bad. It is bigger -227 one you need to replace.
 

Attachments

#13 · (Edited)
I don't remember making that promise as I have not yet had to make that repair to governor.

There have been a couple threads on how to do it by others. If it ain't broke I don't fix it and luck holding so far for me on that problem.
 
#14 ·
Steve,

Any idea if the 164 CarDisc is an adequate substitute for the hardcopy Alfa manual ?

Is the 9000 manual more detailed than the Alfa manual for the auto tranny ?

Thanks.
 
#16 ·
Yes and Yes, paper much easier to read but weighs a ton and is about 1700 pages for the 2 volume 164 manual set. CD also has factory bulletins and owners manual, etc so handy to have.

Paper Saab 9000 A/T 4:2 manual M 1986-95 order #361097 covers tranny much better than 164 manual.

You also need parts breakdown shown on Eriksson Industries
 
#15 ·
The word I get from Steve (I have a broken A/T in the repair queue) is that the Saab manual is head and shoulders above the Alfa manual. But it's not available from Eriksson, or wasn't a few weeks ago. I haven't yet tried Saab sources, but they might be more productive. Our A/T was slipping internally, apparently not just a governor issue, barely working when cold and not at all when hot. If you (or anyone else) know of or find out about something easy which would keep me from having to do a full rebuild, I'd appreciate it.

Michael
 
#17 · (Edited)
ZF service manual

I have found order number for ZF shop manual and I hope to contact them at their IL location and see if I can get a copy but in the meantime I thought I woiuld bump this thread up again.

I found out ZF manual available new for cost of $390 plus shipping so may hold off on getting that one as Nat Wentworth told me again this week that Saab manual much better especially for working on valve body aka distribution box.
 
#18 ·
REBUILT AUTO TRANNYs FOR 164

Not all 164 auto trannys models are identical. The 1964 and later, the LS Automatic tranny with its EIS (ice) option (Q is only 5 speed?), is far more advanced that the one for B or L (again, perhaps only I have turned my 164 auto into car that looks like an S). But both a ZF transmissions made in Switzerland. While I am sure there are some of you who enjoy fooliing with auto transmissions, I pale at the prospect. BESIDES, I have had the privilege since 1984 of representing and trading services with a full service transmission rebuilding factory in Auburn, Washington, that has done the factory warranty repair exchange for BMW, SAAB, etc. (including the infrequent Alfa Romeo) on the west coast for many years. They receive a container collected from all over the far east from Taiwan every month or so to rebuild. They have always kindly redone my friends transmissions, but I've never asked them to do any Alfa transmissions except for me. Still, if someone wants to buy a rebuilt transmission for Alfa Romeo 164 (early or LS) I believe I can get you a deal. They did a wonderful job on my Montreal (also a ZF, but not an automatic) as well as the automatic for my 1991 164B (now an S). As a special gift to me they even took that sideways monster out and put the rebuild back in. I think it runs better than the original, but I only got the car after it was totalled, so I can't honestly say that. I had managed to drive it two years before it went bad, and it only failed then because it split a hose and I ran it out of flud. I am not sure they would think I was doing them a favor in getting them more Alfa automatics to repair, because they let me know mine was not enjoyable. But they are just ZF ransmissions with different mounting arrangements, and they have full testing and checking equipment to be sure their work comes up to ZF's highest factory warranty quality standards. Can't continue such work year after year if not up to snuff. So, call me if you would like to have a rebuild exchange at some decent price. I checked, and they tell me they have one early model sitting half finished right now, missing a kick down. They will take that off the core that gets sent in if it is still good. Otherwise they warned me I will have to find them one for causing them such trouble, and they will start teasing me about my FIATS. Jay
 
#21 ·
transmission wont go into any forwar gear

I have a 1991 164 with 85,000 miles. about 1 month ago when my daughter was driving she started seeing smoke comming from under the hood. she emidietly pulled over. she thought it needed water but it didnt. she started back up but it wouldnt go anywhere.

I found that one of the transmission feed lines had sprung a leak. I had the line repaired and put it back on. Put some transmission fluid in started it up and everything was fine.

Last week when she would start the car it would take a moment befor locking into any forward gear when shifting from park etc. once it got into gear it shifted fine.

tonight she was driving my younger son to basketball and she said it took a little longer to get into gear but then was fine. However when she started going up a hill it wouldnt go forward. I tried to get it to go forward but it wouldnt go anywhere the engine would rev but nothing. it almost felt as if the parking brake was on. It shifts into reverse and works fine. If I rev it it slowly starts to move. any thoughts. I just had the heads rebuilt and put new hoses on did all the work with my brother in law except the machining. the car runs and looks great. also im not sure but the transmission might be overfull.


help needed.
 
#22 ·
The "won't go forward" symptom is what my '91L was doing. The eldest daughter was driving it mostly and had reported the transmission was slipping in forward gears. When I got into the car (cool engine/transm.) I felt nothing out of the ordinary. Naturally. Then she got stranded 30 miles from home when she didn't have a real reason to have gone there. The car was OK for a few miles at a time, but rapidly reached a state where it wouldn't go more than 5-6 miles without starting to slip into undriveability. I swapped in another running auto transm., and it's OK for now. I plan to rebuild the other with parts from Eriksson Industries. But another option is to swap in the pedal box and associated hardware from a 5-speed S parts car. It's just a question of which project gets started when. My wife would prefer to have an A/T car, it turns out, but she's happy with her '92S right now. So if we go with the repaired A/T, I may end up with her red '92S.

Steve (Alfisto Steve) confirms reports he's heard that the Saab ZF HP18Q manual (the A/T) is head and shoulders above the Alfa manual, and even better than the manual ZF put out. (My recollections only -- may be inaccurate)

Michael
 
#23 ·
Who needs a rebuilt transmission?

I just checked again with my client, TRANSMISSION REBUILD CENTER, 1(800) 336-5525. They have a totally rebuilt 1992 transmission ready to ship for someone who will send a core. If you give them my name they will probably give you a decent discount. But because of their warranty they will request that you get an transmission oil cooler. If you burned up your old transmission a bunch of that old burned up bad fluid contaminated with the metal pieces of the clutches, etc., ill probably be trapped in the cooler and should not be reintroduced to the new transmission because it will ruin it. The company gives an instruction on how to attach the one line pumping to the cooler of the transmission and leaving the return line unattached -- i.e., draining into a bucket until the fluid comes through without contaminants. Sometimes that has not proved to be enough, so they want a new transmission cooler. My client is in Auburn, Washington, one of the suburbs of Seattle. They ship transmission throughout the world. Frankly, if you split a hose and ran out of fluid to the point you couldn't move, then you burned up the transmission and need a rebuild. If it worked for a while after you put a new hose on it and refilled it, you might have stopped in time, but contaminated the transmission anyway by running the burned metal bits and old fluid from the cooler through it. Maybe you can do your own rebuild, but sometimes it is nice to get one to put in immediately when you take the other out. Be sure to ask for a deal as an Alfa Romeo lover friend of mine. Don't let them tease you about having a Fiat. Jay in Seattle.
 
#24 ·
taking the big plunge (transmission)

After much prodding I was able to get a more complete picture from my daughter who was driving the car both when the transmission line burst and last week when it started slipping.

My daughter was driving up a grade and stopped at several stop signs. When pulling away from about the 4th stop sign the tranny started to slip. Origionally I thought that she was driving along and all of a sudden the car wouldnt go anywhere just revving as if it was in neutral. Instead it started out from the stop and then the trans started slipping. The car would still go forward up the hill but the engine would rev high as the transmission was slipping. She continued on for a few hundred feet (about) and it was up hill. She stopped the car, and since then nothing at all. It does feel like its trying to go forward but its as if the brakes are on.

After this I spoke with the people at ericksons one more time about my transmission. Since I wanted to avoid the expense of rebuild if possible, I asked them a few times about the stuck valve possiblity. The responce was always the same. "forward clutch".

Ericsons said that when comming to a stop the valves will sometimes stick open. one person at erickson asked how fast she was going before comming to a stop. he mentioned that the 4-3 valve would be the usual culprit but she would have needed to get up to 40 mph before comming to a stop. Which she wasnt. 30 would have been really going fast between these two stop signs. I know as I tried.

Based on what happened when the tranny went dead and the fact that about 1 month earlier it had lost a lot of fluid when the transmission line burst. Erickson's, 3 calls and 1 email later , keep saying the same thing its the forward clutch. I even mentioned that it still has reverse. There take is probably damaged when it lost fluid. and that sped up the end of life failure.

I had the car towed to Italian imports in San Carlos California. They are going to do a full inspection before they send they take the tranny out and send it off to be rebuilt. I really dont want to spend more than I have to. Again from what my daughter told me the transmission was actually slipping and the car kept moving forward under its own power albiet with the engine revving very high.

I did contact the transmission company up in washington but kevin who I left a message for did not call me back. So the 91 rebuilt transmission they have is still there.
 
#26 ·
Something to pass on.

Many good Mechanics have told me and its pretty obvious that ZF trannys run great BUT..their biggest weakness is that they dont handle heat very good and that the cooler they bring many mechs have told me is WAAAAYYY to small for that tranny. A friend of mine who's Porsche guy told me that these trannys can last a long time if you can get them to run about 50 to 60 degrees lower than normal engine Temp. So thats probably off the 180 mark try to get it down to 100 or 110. I kind of thought about it:rolleyes:. The man does know what hes talking about because He has worked on Alfas and Porsche's pretty much all his life. Hes a very nice man 60 years old. SOOOOO I tried something to prove myself and pass it on. What I did was I pulled the tranny thermo off and unscrewed the brass nut or the actuator itself I had to heat it up on my stove with water to get the little metal wire if you will to come out which opens the thermo.I measured how far it came out cut a nail put in there to keep open at all times screwed brass nut back and installed it back in engine. I went for I ride..AND HOLY ****!!!! :eek:What a Difference!!!:eek: Talk about smoother Shifts!!:eek:BTW I also made sure I flushed the cooler itself to make sure it was clean inside before I installed it. Tranny definetly runs a little cooler NOT cold but warm although the fan will not kick in until it reaches 180+ but as you drive the airflow really keeps it good dont have to worry about it running to cold because engine itself keeps it warm. Just an Idea to Pass on. I told my friend about it He Just smiled.
 
#30 ·
:eek:
What I did was I pulled the tranny thermo off and unscrewed the brass nut or the actuator itself .
Danny,

What is this device of which you speak ? Can you explain further .

Is there a valve in the ZF to regulate transmission fluid flow through the cooler (like an engine coolant thermostat) ???
 
#27 ·
So...does this mean that the basic air-cooled tranny intercooler should be retrofitted to an engine coolant intercooler? This would give a lot of heat transfer and keep the oil down to 180-190F. Thoughts? This would mean an alternate radiator, as I see it. But it might be worth the trouble for A/T cars, rather than losing the car when the A/T fails which is what often enough happens.

Michael
 
#29 · (Edited)
My guess is a resounding NO ! The last thing you want to do is transfer all that heat energy from the transmission into the engine cooling system.

Here in Australia a lot of 4WDs and tow vehicles have additional transmission coolers fitted, and in a lot of cases the factory radiator-incorporated cooler is bypassed. Helps keep engine temps in check along with the transmission temps. I guess in a cold climate a radiator tranny cooler would allow the transmissionn fluid to get up to operating temp faster, but this is rarely an issue over here.

Buy a quality (large) transmission cooler, fit it correctly, maybe incorporate an adjustable thermo switch for the fan, and service the transmission regularly, and I reckon you'll see great results.

I don't know about the ZF, but a lot of tranny's don't like to be manually shifted (held in intermediate gears) and will quickly get hot if they are driven in this manner.

If a transmission cooler incorporates it's own thermo-controlled electric fan, it can be fitted almost anywhere and in any orientation. I feel this is a preferable option to sandwiching the cooler along with the radiator and AC condenser and expecting the engine fan to draw sufficient air through the whole shebang.
 
#28 ·
Two comments. I think that many of these auto trannies benefit from having the fluid changed at least once a year, as with the Chrysler van versions. Those can get hot and burn the fluid which causes it to not work nearly as well. Brother in law has a set of really burnt gears from their Chrysler van. The mechanics said it is essential to change that fluid.

As for the manual on a disc, I just bought an old used laptop really cheap, and use the disc in that. Weights one heck of a lot less, and easy to carry around in the shop. I may also just print out the relevant pages if I'm doing a repair.