What Brand Of Motor Oil Do You Use In Your Toy

Article from another Forum;

The definitive Marc Haibeck's article on this subject says correct ZDDP is in Mobil 1 High Mileage or Amsoil - http://www.zr1specialist.com/HAT W...5 Engine.pdf -
"Most modern GM engines use roller valve lifters. They have short timing chains to drive a single camshaft or dry belts to drive multiple camshafts. The need for EP protection for these engines is decreasing. Japanese carmakers that like to use long metal timing chains are evaluating the effects of the future oil standard on their designs.
My concern is for the flat valve lifters, the camshafts, the timing chains and the sprockets in the LT5. I believe that the SM oil for new cars is not appropriate for the LT5. The Mobil 1 Oil Company has also recognized the needs of flat lifter engines with respect to their products. They recommend their reformulated 15W-50 productvi for engines with high-tension valve springs. I think that 15W-50 oil is too high in viscosity for the LT5. The Mobil 1 High mileage products are also acceptable for the LT5 engine.

The Amsoil Company has addressed this issue with a product that is specifically designed for engines with flat valve lifters and high tension valve springs. It is formulated with high phosphorus and zinc protection. It meets the API SG specification that was used when the LT5 was designed. The product is named AMO 10W-40 Synthetic Premium Protection. It takes a two-pronged approach, higher EP additives and superior film strength due to the higher viscosity.
AmsoilAMOZDDPspecifications: Phosphorus 1265 ppm
Zinc 1378 ppm
Comment: Recommended for the LT5 engine. Also for other engines with high tension valve springs.
 
yup, like i said, flat tappet cams need zddp. delco engine oil supplement is only about 8 bucks a bottle. add a 16 oz bottle to 5 litres of oil and you're more than safe.
 
I agree with Bearly Flying in his assesment in regards to the correct oil to use in a flat tappet engine. I always used Mobil 1 10w/30 then finally did some checking and reliazed the reduction of phos. and zinc in todays oil. I tend to have faith in Mark Haibeck's test he performed and decided to switch to Mobil 10w/30 High Milage oil as we can't obtain Amsoil here in Ontario. I recently went to Mobil 1 site and they recommend I use 5w/ 30 in my 1990 ZR-1. Now I am confused what grade of oil to use. Suggestions would be appreciated. Thank you
 
Actually Buckhorn, He has 4 flat tappet Cams. The C4 ZR-1 only came with the LT5 motor.

Cruizin, I believe the Mobil 1 "High Mileage" line of Oil meets the spec for the LT5.

Another thing to watch for is the Oil filter, there have been some problems with the anti drain back valves in some of the filters. I use the AC Delco PF 970C.
 
The only reason I mentioned the Oil filter is because the LT5 has the filter upside down, it is not a concern for any other motor. If the drain back valve leaks back in an LT5 you will have several seconds of no oil pressure on start up, while it refills the filter case.

With the 4 cams,flat tappets, 32 valves and long timing chains it can get expensive really quick.
 
VINDIC8R said:
Okay, I'll bite. What the heck is zddp?
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it is a zinc/phosphorus additive that is in the engine oil. it is crucial to have an adequate amount for lubrication of flat tappets and cam lobes. a roller engine doesn't need it and consequently the amounts have been dramatically lowered in modern oils as it has been found to be hard on catalytic converters. unless you have a roller cam in your older engine.......you're rollin' the dice.
 
ZDDP=Zinc dialkyldithiophosphates.

The main use of ZDDP is in anti-wear additives to lubricants such as greases, gear oils, and motor oils, which often contain less than 1% of this additive. It has been reported that zinc and phosphorus emissions may damage catalytic converters and standard formulations of lubricating oils for gasoline engines now have reduced amounts of the additive, though diesel engine oils remain at higher levels.[3] Crankcase oils with reduced ZDDP have been cited as causing damage to, or failure of, classic/collector car flat tappet camshafts and lifters which undergo very high boundary layer pressures and/or shear forces at their contact faces, and in other regions such as big-end/main bearings, and piston rings and pins. Roller camshafts are more commonly used to reduce camshaft lobe friction in modern engines. There are additives, such as STP(R) Oil Treatment, and some racing oils such as PurOl, Brad Penn and Valvoline VR-1, which are available in the retail market with the necessary amount of ZDDP for engines using increased valve spring pressures. The same ZDDP compounds serve also as corrosion inhibitors and antioxidants.

Courtesy of Wikipedia.
 
Thanks Buckhorn76 and jabroni. Now I can sound intelligent about zddp. There isn't going to be a quiz later is there?:p
 
......maybe we should just say, Check with your owners manual. :D

And for all you guys without an owners manual.....Google?
 
Riley P said:
......maybe we should just say, Check with your owners manual. :D

And for all you guys without an owners manual.....Google?
Click to expand...

good advice riley, but.......the owners manual for the older cars lists oil that hasn't been available for years. if you don't use a proper additive you WILL wipe the cam lobes. the dipstick in my car is stamped api sf, probably hasn't been available since the early/ mid 90's. spreading the word about this has become sorta' a personal crusade with me. :rofl:

p.s. api sf is considered obsolete by the american petroleum institute and is recommended for engines 1988 and older.
 
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Last night at the Uxbridge cruise, I talked to a guy that I haven't seen in a few years. He's had the same '70 Z/28 since it was about a year old. After wiping a couple of cams over the last 10K miles, he went with a street roller cam. Costs a few bucks but money well spent. The car performs better too. He's happy and doesn't have to worry any more.
 
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damn right keith. if you're going that far into the engine - put in a roller. there are many reports of crate engine warranty issues because of flat tappets and improper oil. especially critical in the first thousand miles of break in and the initial firing of a fresh motor. once the cam lobes and lifter surfaces develop a wear pattern......kiss it goodbye.
 

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