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I'm about to purchase a 1990 ZR-1 with 165,000 miles on it and I normally use M1 High Mileage 10w40 + Lucas High Mileage Oil Stabilizer in my L98 C4s. I actually use this M1 + Lucas combo in all of my old cars and it seems to protect well and minimize oil consumption. Is there any reason NOT to use Lucas in a high mileage LT5? Note: I’ll use a Wix 51324 oil filter on the LT5. Thank for your help and advice! I’m super looking forward to picking up the ZR-1!!
I'm about to purchase a 1990 ZR-1 with 165,000 miles on it and I normally use M1 High Mileage 10w40 + Lucas High Mileage Oil Stabilizer in my L98 C4s. I actually use this M1 + Lucas combo in all of my old cars and it seems to protect well and minimize oil consumption. Is there any reason NOT to use Lucas in a high mileage LT5? Note: I’ll use a Wix 51324 oil filter on the LT5. Thank for your help and advice! I’m super looking forward to picking up the ZR-1!!
In the first place, the LT5 ain't no L98.That is not "high mileage" for an LT5 that has been properly maintained up to then. The thing is, the ZDDP levels recommended @ the time of the LT5's intro was in the 1100/1200 PPM (zinc etc.) The ZDDP level in recent oils (API "SM, SN, etc) has been made possible with the use of roller tappets. The LT5 has flat tappets.
The oil (I guess) most of us use is either a full synthetic or some use a synthetic blend with a ZDDP of 1000 ppm minimum (100/1200ppm is a better choice, far as avoiding scuffing resulting mostly with flat tappets and high rpm. The stock LT5 will spin up to 7100 RPM, which is just a leeeetle bit more demanding than that of the L98.
Marc Haibeck (the ZR1 Specialist) recommends Amsoil synthetic 10w-40 / ZINC formula. Yeah, it is pricy, and for that reason others use other similar oils with similar additive contents. However, Amsoil claims ~ 10,000 miles between oil/filter changes. I've been in the 3000 to 5000 change interval all my life, and changing it more often that 10,000 miles doesn't hurt a thing (usually every season or at 3000 miles. She's worth it!)
I go with Marc's suggestion and stick with the Amsoil w/o any (gimmicy) additives. And, since 2007 and 30k miles, my compression* and oil pressure haven't reduced from the day I bought her - some 40k miles and 15 years ago. (& now is fully ported w/ headers, etc. and makes 510 hp @ the crank.)
You do as U see fit. But, it takes far more time and mileage testing (sample size) to prove or disprove the benefits of switching from one oil regime to another. So, I'm afraid we mortals have to follow the successes of others and hope we followed the right example(s), and I'm no chemical engineer either. But, if it is synthetic (i.e., very stable viscosity over temperature), has ZDDP in the 1000 to 1300 window (not too little and also not too much), and you change the oil and filter regularly and avoid those gimmicy additives, you'll fold in with the majority of long time ZR-1 (LT5) users, methinks.
I third the oil recommendation. There are other good ones as well. I would not use any "magic" additives. Most of them are just oil themselves and only serve to dilute factory additive packages and sometimes drastically change the viscosity of the oil.
I third the oil recommendation. There are other good ones as well. I would not use any "magic" additives. Most of them are just oil themselves and only serve to dilute factory additive packages and sometimes drastically change the viscosity of the oil.
This guy "GETS IT". Why do people pour unknown potions into their engines? Or think doing that is a "good" idea?? That crap solves two "problems"; 1. Over weight wallet, and 2. psychological problems.....not actual ones.
Amsoil,Bosch filter done. I will use nothing else for as long as I can find these products. This combination seemed to quite down the cam chains compared to the other products I've used.
Amsoil,Bosch filter done. I will use nothing else for as long as I can find these products. This combination seemed to quite down the cam chains compared to the other products I've used.
I've been running the Wix filter (Napa Gold) with good success. It is also on Mark H.'s recommendation list.
Hi OP, you are going to love the lt5. I too had several l98’s and skipped over the lt1/4 went to zr-1. i take my Z to the track for lap days, i love it!! you will love it.
i use mobil 1 5w40 or 10w40 cant recall. im not to concerned about it.
Marc built the LT5 in my Z . I defer to his recommendations of the Amsoil AMO 10W40 full synthetic and the Bosch oil filter . Although he states that the current Mobile 1 with reduced package is still good and you won't see much appreciable wear .
There are test showing that most additives reduce an oils protective qualities and aren't needed . The test were using levels of the additives recommended and not higner than what you would use . Most oils recommend not using any additives in their oils including Amsoil . So whether you run an oil with a higher level of zinc than the current oils or just a really good full synthetic or conventional oil change it more frequently. Don't go long on your intervals. Oil is cheap compared to a rebuild period .
I think some oils have way too much zinc. I wouldn't run more than what's in say the Z Rod . Tests have shown that the Amsoil Signature Series 5W30 is really good for protection. Not all oils are API certified as the testing is very expensive especially to certify a diesel oil my cost 3/4 to 1 million dollars for several years .
05-13-2022, 12:52 PM
165k LT5 & Lucas High-Mileage Oil Stabilizer
This guy "GETS IT". Why do people pour unknown potions into their engines? Or think doing that is a "good" idea?? That crap solves two "problems"; 1. Over weight wallet, and 2. psychological problems.....not actual ones. 
