B!@cK 86 V3tt3

Yep. I think ima change my oil pretty soon. Sure it needs it. I am going to go with Mobile 1. Full synthetic. Can I use 0w-40??? or 10w-40??? Its winter here in N.C. and its not horribly cold but it can be chilly. I just want the best for it. So is the 0-40w ok?

bogus

stick with 5-W30. That will work just fine. It's a good multipurpose weight that will work in many temp ranges. The L98 isn't built to the tight tolerances that modern engines are, hense a 0 weight oil is just too thin.

B!@cK 86 V3tt3

Mobil 1 synthetic is ok though? When I first got my car last year in june 15 days after I bought it, the bearing rod broke and tore up the block....We changed the oil the day before. Penzoil synthetic and a K&N oil filter.....Hmm. My dad said it was because of the synthetic...Can I get some clarifacation on that? And I know that sounds stupid but hes against new stuff like that. Old fashioned I guess....

RRT vette

I'm using 10w30 with an AC Delco filter in my 86E.

jsavoy

Oil starvation, low oil pressure, excessive clearances in the rod bearings due to high mileage, wear or neglect from the previous owner not changing the oil / filter often enough to name a few can all be causes. I'm guessing that the engine rebuilder didn't say or you went with a short block. I'm with Bogus, Mobile 1 5W-30 is what's been used in mine since birth (per the mx records) and it's what I'll continue to use.

B!@cK 86 V3tt3

It had 95,000 miles on it and its 20 years old. Either he replaced everything with AC delco or they were original parts. When we got it home battery looked old as crap and it was leaking acid. When the starter went out, the technician said it was original...Almost everything was original. I believe thats why everything is breaking. Alternator was AC delco. It had a AC delco oil filter on it also. When we changed the oil the first time, it was a little dirty...sooo....The mechanic that redid the block had no idea why it broke...Age I suppose or like you said negletct. This engine better last a while.

jimg's'93

That rod bearing letting go was a coincidence, even if the oil did have an adverse effect on the engine, it would take more time than that (loss of pressure the exception). Sounds like the previous owner wasn't too kind to that ride.

I use Mobil1 Synth and Mobile1 filter in my LT1...10w-30 year round...every 5k.

Trog

Not sure when they started it but my '90 came w/ Mobile1 5-30 from the factory.

1988roadster

Mobil has an interactive web page (Q&A) When I purchased my 88 I asked for a recomendation since my vette has 114,000 on it. Mobil recomended I use 10w 30. The web page has a lot of good information and dispells a lot of false beliefs as well.

Kool88vette

I use Mobil synthetic 5w30. That is the recommended weight for my 88. I wouldn't use synthetic on a high mile engine and 10w30 should be good for high miles.

B!@cK 86 V3tt3

Well it looked pretty nice. Looks can be deceiving. I think it was run hard. He mustve goten rid of it once he got the enjoyment out of it or he thought it was going to blow...Damn lucky me.

c4cruiser

GM started using Mobil-1 synthetic in 5W-30 in 1992 when the LT1 motor came out. Prior to that the factory fill was regular dino oil, not synthetic.

Synthetic oil didn't even appear in the ZR-1 until 1993.

IIRC, GM said that using 10W-40 oil in the small block motors would void the warranty. No real idea why as that weight is apparently OK in other motors.

B!@cK 86 V3tt3

No synthetic on high mileage cars? Why?

86GoldProject

Switching to synthetic on a high mileage engine can cause leaks and cause things to get plugged up with sludge, this is because the synthetic actually cleans too well and starts unsticking buildup that may already be in the engine sometimes causing it to plug up other things like oil pump pickup screan, oil filters etc. It doesn't exactly cause leaks, it just allowed leaks that were already there to leak better due to the cleaning away of the sludge thats plugging them up and slowing/stopping the leak. There are many different opinions on this topic. Personally I wouldn't hesitate to switch to synthetic on a high mileage engine provided its been well maintained and isn't a sludge bucket, the only problem is its hard to know for sure unless you're the one who put all those miles on it and knows how it was maintained

jimg's'93

Unless that high mileage car has always had synthetic in it.

B!@cK 86 V3tt3

It had a new block in it. Its got about 40,000 miles on it or so??? Its been run on penzoil so far. So......

c4cruiser

If you have been changing the oil and filter regularly (every 3000 miles or so) you should not have any problems going with a 5W-30 synthetic oil.

86GoldProject

I'd say go for it. Switched to synthetic on several cars of mine with much higher mileage with no adverse effects.

Road Agent

No need for synthetic oil in your car.

B!@cK 86 V3tt3

True there is no need for it but I have heard synthetic last logner in heat than does the dino. Thats the main reason im doing it. Also it has detergents which will hlep out any dried seals?