Want to switch from Rotella T 15w-40 to a full synthetic oil. Any ideas?

[my78chevyc10]

When I purchased my 1978 Chevy C10 the guy told me to run this motor oil because of the aftermarket cam and lifters and I have no clue what other reasons, but he also said synthetic breaks down in the engines heat. I was wondering what is a good, cheap, full of ZDDP, synthetic oil and if I should make the switch over. What oil would be recommended (since I live in Arizona where it's always hot)?

[screamin86]

What cam is in it? I've only ever ran rotella for break ins and switched to regular conventional oil after that. Conventional oil is what breaks down under heat if I understand correctly synthetic protects against that.

[Russ130]

Mobil 1

[grinder1989]

I always break engines in with Comp Cams break in oil and 5 quarts of conventional oil.  This allows everything to break in properly.  After about 1000 miles, I change the oil and put the same stuff in.  After 3000 miles, I run Royal Purple 10W-30.  Rotella is a bit thicker but it works just as well.  I'm sure that the zinc levels are lower the RP but it's good oil for the money.  There was a big thread over on S10-V8.com over it.

[choptop]

I've never heard of synthetic oil breaking down. Oil doesn't break down, it gets contaminated thus changing the viscocity and lubricity characteristics. I've been running Amsoil for years and love it. I have seen engine temps drop and reduced oil consumption in a few, primarily my 01 crewcab with the 8.1. Depending on mileage, synthetic is fine for your engine. If the motor is broke ine good, I wouldn't have any concern about switching

[my78chevyc10]

The cam is a Melling cam, not sure about the model but when I bought it from the guy he was like "DON'T RUN SYNTHETIC" but I don't know why you wouldn't. I've read the Mobil 1 (like Russ130 recommended) has quite a bit of zinc. I'm also wondering if this thick oil is causing a ticking sound under my left side valve cover I'm thinking it's a hydraulic lifter problem or what. The engine was recently rebuilt by the guy who sold it to me who worked at a machine shop.

[screamin86]

Sounds like it needs a valve adjustment.

[polish pete]

well this is just my opinion but if your not going high mileage there is no need for synthetic oil or anything too fancy, its just oil imo.

[Dr_Snooz]

Sorry, I don't know much about cams, but is it a flat tappet cam? If so, you're in to the whole zinc and ZDDP issue. Apparently, if you don't use an oil with enough zinc, you risk having valve train failures. I'm not educated enough on the issue to advise you, but I wouldn't risk using the wrong oil without reading a lot more about it.

Here's a starter link for you: http://forums.corvetteforum.com/c3-tech-performance/2484100-list-of-flat-tappet-oils.html. The irony here is that, according to the discussion, Rotella no longer has enough zinc for flat tappet cams either.

[screamin86]

Something with the epa I believe started limiting zinc in all motor oils now. Now when I do cam break ins I use straight 30wt non detergent and a bottle of that lucas zinc additive.

[bobcooter]

If you plan on changing your oil every 3000 to 5000 miles a good conventional oil l will do fine. I personally like Valvoline. Synthetic is OK too but, you said your engine was recently rebuilt. I would not make the switch until I had well over 3000 miles on the rebuild. Also, some people say that Mobil 1 is good for 10000 miles before needing to change. That's what we were doing with out company trucks, then someone said something needing a special filter to go that far.  You need to check on this if you decide to go that route. My honest opinion is that if you are doing normal driving and you plan to do the maintenance on your truck yourself, synthetic is a waste of money.

[screamin86]

+1 on valvoline I run that in all 4 of my vehicles.

[grinder1989]

If you plan on changing your oil every 3000 to 5000 miles a good conventional oil l will do fine. I personally like Valvoline. Synthetic is OK too but, you said your engine was recently rebuilt. I would not make the switch until I had well over 3000 miles on the rebuild. Also, some people say that Mobil 1 is good for 10000 miles before needing to change. That's what we were doing with out company trucks, then someone said something needing a special filter to go that far.  You need to check on this if you decide to go that route. My honest opinion is that if you are doing normal driving and you plan to do the maintenance on your truck yourself, synthetic is a waste of money.

Synthetics are the only oils that contain enough Zinc for a flat tappet cam engine.  If you have a roller, no, you do not need it but a flat tappet cam NEEDS to have the Zinc.  Why do you think all engines all rollers these days?  Oil can still be produced cheaply without potential engine failure.  Synthetic will not break down as easy, has lots of Zinc and is far superior to conventional oil.  You should research it yourself.  It's quite an interesting topic.  The only use conventional oil has is properly breaking in an engine.  After that, it's useless.

[VileZambonie]

http://www.royalpurple.com/

[my78chevyc10]

Alright I did fix the loose rocker arm takes care of that problem. The whole choosing an oil is interesting to me and I've been looking into which ones to choose. Most of it seems like a personal choice but then it breaks down into how much zinc is included in the oil and how much you're willing to pay I guess. Thanks for all the replies everyone I'll stick with this oil for now until I research about some of the oils you guys suggested and find out which best suits me and my set-up.