Alfa Romeo Forums banner

Are 5W/40 weight oils suitable for spica spiders?

943 Views 4 Replies 5 Participants Last post by  marco246
Does anyone use 5W/40 weight oil in their spiders I know it's a lighter oil than most Alfa owners use, but it's readily available and offers start up protection due to it's cold weather pumpability. Yes I do fear that it may allow oil seepage past seals & gaskets that have grown old and used to having a thicker oil? Anyone care to share their experience? Thnx
1 - 5 of 5 Posts
..on my last/late 78 spider. i ran 20/50 all year long.. but then here in cali. i only gets down to upper 20's at the most and back into the 50's in the day time..
I use Shell 15w40 Rotella T. I know it's a diesel oil but I've had good results with it.
I used to use Castrol GTX 20W50 in both my Alfa's, until the story about lowered zinc content hit the Internet. I now switched to Shell Rotella T 15W40 as well, that supposedly still has a decent amount of zinc. I live in Texas, so I'm less worried about the cold start, and would not want anything thinner,,,I'm more worried about the high end. Athough I have not driven on a very hot day with this oil, oil pressure seems better than with the Castrol....I realize this is subjective, reading values from a gauge that is probably not the most reliable instrument out there......This oil is inexpensive and readily available. You may want to do a search on this board, there really is a ton of information on oil choices:cool::cool:
The advantages of a 5W-40 oil are that it provides good lubrication hot or cold. Your engine oil will come up to operating temperature more quickly and consequently there will be less wear on the engine following a cold start. The disadvantages are that all 5W-40s are synthetic and therefore expensive compared to conventional oils and that you might get seepage past old seals.

I am not convinced that lower zinc levels in newer oils presage disaster, but if you want to play it safe use a heavy duty engine oil like Shell Rotella T Synthetic 5W-40 rather than a synthetic passenger car motor oil in that grade.

Like Velocemag and Peter I'm using a 15W-40 HDEO (Chevron Delo in my case). Even though I just put in a new rear main, the engine still leaks oil from an undetermined source, so I can't justify the expense and presumed additional leakage of going to a synthetic at this point.

There are, however, plenty of folks happily and successfully using synthetics in their Alfas. You'll just have to experiment to see if you're one of them.
See less See more
1 - 5 of 5 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.