Racinfan83

Did a forum search and didn't find much info on this... so I shall ask
I am used to changing my own oil on my vehicles. Don't know much about this beast - so hoping u guys can tell me. I have the AC PF970C filter already, and I use Mobil 1 10w30 in my other vehicles anyway so good there. How many drain plugs are there, will I need to do anything special with the cooler or filter, how many quarts does it take? Any other hints regarding the oil change process? Thanks....
I also have this up on the ZR-1 registry so please reply to one or the other... Still learning who is who and how many more people are on which forum...

Dynomite

blownrunner

From memory and what I read, the engine holds about 12 quarts but only about 8.5 quarts are drained during an oil change. I use signature series from amsoil, a service rep said it meets the engines older standards. I also use their Wix filters, any filter for this engine I believe has to be designed to be used upside down. There is only one drain plug on the oil pan, none on the cooler. Do not use an engine flush as it breaks down oil and seeing how you cannot drain all the oil out, you will still have some flush remaining in the engine to contaminate the new 8.5 quarts. Check the oil level after one hour as per owner manual. There is also a procedure to reset the change oil light which does not sense the oils condition, but rather a time interval. Once again, from memory...

Racinfan83

No I would never use that flush stuff... I already have the filter which is the dealer spec and also the latest reccomendation from Marc Heibeck - and a bunch of Mobil 1 I got for like $5.99 a qt, so I guess I will use it first and then go from there. I was mainly curious about capacity as my dlr service manual said 8.6, but didnt provide any assistance on how to do the change. And I have seen people post anywhere between 8.6 and 12 qt capacity...

C66 Racing

A consideration for your motor oil is the amount of anti-wear additives in the oil. A lot of ZR-1 guys use oils such as the above mentioned AMSOIL 10w40 that have higher levels of anti-wear additives than allowed by current API SN specifications.

From 94-97, the API SH spec allowed up to 1200 ppm phosphorus for 5w30 and 10w30 and didn't address other 30 grade viscosity like 0w30. In 97, API SJ dropped the limit to 1000 ppm, but still did not address 0w30. In 01, API SL kept 1000 ppm phosphorus, but added 0w30 to the spec. In 04, API SM further dropped the limit to 800 ppm, but for the first time set a floor at 600 ppm and advertised that oil's were better. Essentially they were capping how much phosphorus the better oils could have and mandating the lowest amount the cheapest oils must have. The current API SN spec still has the band 600-800 ppm phosphorus.

Unfortunately, phosphorus, along with zinc, in a compound called ZDDP, or or zinc dialkyl dithio phosphate, forms an oil's primary anti-wear additive. The reason behind this is that phosphorus slowly poisons the cats and prevent the catalytic exchange that allows them to function properly. To ensure auto companies could meet the EPA's 100k+ emissions requirements, the API has slowly been dropping the limit on phosphorus.

So, any oil labeled to meet the current API SN spec will be limited to 800 ppm max phosphorus. This impacts how well it will be able to perform in anti-wear, such as might be seen in your bearings under heavy load.

You can get around this a few ways. High Mileage oils do not need to meet the current API SN specs. Mobil 1 High Mileage 10w30 has 1100 ppm zinc, 1000 ppm phoshorus and if you are dedicated Mobil 1 user, I'd recommend the HM Mobil 1 over the regular Mobil 1.

AMSOIL's offerings for this market:
AMSOIL Z-ROD 10w30 Synthetic Motor Oil (Product Code ZRTQT)
(zinc – 1440 ppm, phosphorus 1320 ppm)
AMSOIL SAE Synthetic Premium Protection 10w40 (Product Code AMOQT)
(zinc – 1378 ppm, phosphorus 1265 ppm)

More than happy to get AMSOIL products for forum members at dealer wholesale pricing, about 25% below retail, via the AMSOIL Preferred Customer Program. Drop me a PM if interested.

USAFPILOT

Anyone have the details on Mobil 1 Extended Performance? I use that along with its filter.

C66 Racing

With regards to the anti-wear additive level, the Mobil 1 EP is the same as regular Mobil 1 as they both meet the current API SN spec. Mobil 1 lists the zinc as 900 ppm, phosphorus 800 ppm:
http://www.mobiloil.com/USA-English/...duct_Guide.pdf

I think how this impacts performance in highly stressed portions of your engine can be seen by the High Temp High Shear viscosity (HTHS) which is a meausre of the oil's viscosity at 150C (300F) under shear. Some oil companies report HTHS. Here are the values from Mobil 1 and AMSOIL's corporate websites:

- Mobil 1 10w30: 3.0
- Mobil 1 EP 5w30: 3.0
- Mobil 1 5w30: 3.1
- AMSOIL Sig Series 5w30: 3.2
- AMSOIL Sig Series 10w30: 3.2
------------------------------------
- Mobil 1 HM 5w30: 3.3
- Mobil 1 HM 10w30: 3.5
- AMSOIL Z-ROD 10w30: 3.6

The oil's above the cut line meet the current API SN spec, those below don't due to zinc and phosphorus higher than allowed.

FYI, the main difference between the Mobil 1 and Mobil 1 Extended Performance is the EP has more detergent/dispersant additives that allow the longer advertised oil change intervals.

Racinfan83

Good tips! I was going to change it myself - but the day I was going to do it I had to take it to the GM dealer for them to swap out the antenna they bent. Got over there and they had the wrong one, so they offered me a free Mobil 1 oilchange and a tank of gas. So I let em do it... That said however - they did put a cheapo Fram filter on it - which I promptly took off and swapped with the AC filter I had. I prob won't change it again for a while. The Dirt Mod I work on has Schaeffer Oil as one of the sponsors - and the rep told me he would get me a deal on their Supreme 7000 oil. I looked at AMSOIL online and quite frankly - I can't afford $10 a quart when I get the other for less then $6. I do appreciate the info though - I like learning about this stuff...

A26B

Be sure & check your oil in the morning....cold. Commerical oil changes in the LT5 usually result in overfill.

Z51JEFF

Amsoil and the Bosch filter is all I use.Ive used the Mobil 1,several different filters and what Im using now really quits down the cam chains upon startup.

Fully Vetted

I noticed the same thing. Now I use nothing but AMSOIL. In fact, my order of 16 qts just came in from Brad (C66 Racing) last week. Some say AMSOIL is expensive. I say no...rebuilding an LT5 is expensive. Good oil is cheap by comparison.