GC in a 5.7L pushrod V8 Silverado?

[williar]

I drive my '95 Silverado with the venerable 5.7L pushrod V8 about 5K miles/year; hauling a 2800# camper in the summer and short trips to the dump the rest of the year. I've been running Pennzoil 10w30 in the summer and Pennz 5w30 in the winter with a fall & spring OCI. Would I be better off using GC with an annual OCI?

 

[B00SS]

GC is being run in quite a few 5.7 here, including the LS(x) versions. UOA’s with the green look great. Hopefully someone will post up with the gold soon.

 

[williar]

Yes, I use GC in my car but it gets alot more use. I guess the issue is should I have one OCI per year with GC or two OCIs a year with dino?

 

[pscholte]

Once a year with GC...for sure.

 

[DeaconBlue]

I really like it in the GM 60 degree V6 engines. It sure quited them down (both the valve train and pistons) on cold start-up and they seem to idle much smoother. The mileage looks to be better than with the M1 SS as well.

 

[williar]

Bought the GC today for the pickup, and 16 qts of M1 tranny fluid & 3 qts of M1 75w90 diff. lube. Thanks, guys, for the advice!