GMC 1500 Sierra Oil Leaks

I own a 1995 GMC 1500 Sierra Pickup, with 135,000 miles. I’m the original owner and have done all scheduled maintainence. The vehicle has been very reliable. However, over the last 18-24 months the engine (5.7L V8) has developed a mysterious oil leak–the engine burns approx 2-3qts of oil over a 5000 mile span. Oil apparently leaks into the cylinders and fouls the plugs—fouling is significant in 10,000 miles (driver’s side plugs are heavily fouled with hardened, calcified oil buildup—passenger side is clean). There is no sign of leakage on the outside of the engine—no puddles on the garage floor. No sign of blue smoke from the tailpipe. Engine runs fine–good acceleration and reasonable fuel economy—until the plugs get fouled, then the usual “missing”.

My mechanic is stumped–he’s never seen plugs get so fouled in such a short period of time (10K miles). He believes the problem is either faulty oil rings on the left bank of pistons or alternatively, a faulty valve train, but he tells me any repair would be cost prohibitive (truck is probably only worth $5K). He tells me the engine is not likely to fail as long as oil levels are maintained. He tells me to increase oil change frequency to 3K (I’ve historically changed at 5K) and watch oil levels closely between changes—he also tells me to keep a quart or two of oil in the cab at all times. He believes that if I closely watch oil levels I should be able to drive the vehicle for several more years without serious reliability problems.

I’m a little freaked out by oil leaks of this size. I’m OK with more frequent LOF, but I worry about oil ring failure and getting stranded somewhere. Should I just up my Prozac dosage and drive, or do I need to look for a new truck? Thanks,…

You need engine mechanical work, I don’t think you will get stuck as you seem to have a handle on the time frame (it could get shorter) and you still can drive on a miss.

Why not carry a set of plugs and the tools to change them?

My 2004 F-150 private party sale price is only $4400.00, so I don’t think 5K is what you could get for your 95,just to cheer you up.