I have a 98 GMC k2500 pickup with vortec 454. It was a warden government truck, never worked and had every 3000 mile conventional oil changes with 5w30 until I got it with 103k I ran M1 10w40 in it from then on, and used it to to a car trailer at highway speeds. I am in Florida so very hot all the time. Changing oil about every 5k with mobil filters. These have injector issues and intake gasket issues, and I changed the injectors out with bosch units and ac delco factory gaskets. Also had the computer re flashed for more timing and to increase shift firmness and have OD come on at a higher speed.
I started getting a lope or miss which progressed to a tapping, I narrowed it down to a cylinder, it had slop in the rocker arm. Pulled the intake and found several chewed up lifters. So I changed the cam and most of the lifters, it was a terrible job, had to drop the front axle, pull the core support, ac, ect. I don't want to do it again.
It is all back together and running great, on m1 10w30 this time.
I know GM used roller lifters and M1 oil since 92 in corvette without issues. But these 454 engines use exhaust rotators and have very low spring pressure. They also have less lift than the LT1 corvettes, which is absurd. And I have read that some of these 454s had cam hardening issues causing them to go flat.
So is there any chance that synthetic oil could cause a roller lifter to glide rather than roll and cause failure?
I started getting a lope or miss which progressed to a tapping, I narrowed it down to a cylinder, it had slop in the rocker arm. Pulled the intake and found several chewed up lifters. So I changed the cam and most of the lifters, it was a terrible job, had to drop the front axle, pull the core support, ac, ect. I don't want to do it again.
It is all back together and running great, on m1 10w30 this time.
I know GM used roller lifters and M1 oil since 92 in corvette without issues. But these 454 engines use exhaust rotators and have very low spring pressure. They also have less lift than the LT1 corvettes, which is absurd. And I have read that some of these 454s had cam hardening issues causing them to go flat.
So is there any chance that synthetic oil could cause a roller lifter to glide rather than roll and cause failure?
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