Very high miles

[bdja]

My 2000 Sierra w/4.8 has 387,000 miles and now has a noisy lifter. With winter approaching, the noise surely will get worse in the mornings. I bought it new and want to keep it without having to have an overhaul. I need opinions on oil additives or RP, Amsoil etc. I've been using Valvoline MaxLife 5W20, with Fram filters since 80,000 miles.

Any help is much appreciated.

 

[Bill325]

I've had some luck quieting noisy hydraulic lifters by adding Rislone additive to the crankcase. If the lifter is noisy due to being clogged with deposits, the additive could help. However, at the high mileage of your engine, the lifter could have mechanical problems too. It may also be worthwhile to readjust the lifter by going through the procedure for setting the rocker arm pivot nut. You may find some unusual wear problem on that particular lifter/rocker/pushrod assembly.