I have a 1989 GMC. This truck has an excellent maintenance record. the exhaust needs replaced; Y pipe to rear bumper. is it better to replace exhaust manifold also or pay to have it fixed with original manifolds? ’89 GMC 1/2 ton,305 motor, valve seals leak slightly, needs rear main seal, @90,000 original miles, runs very well though: is it worth fixing? estimates of @ 1,000$ to fix exhaust only. please advise, thank you.
Hey there David
I would visit a exhaust/muffler shop like Midas if you have one in your area. See if they can repair the y pipe, or buy one from a dealership and have them install it. You really dont want to replace the manifolds, that can turn into a big and expensive job that would not be cost effective on this vehicle. 🙁
I would add a can of Engine Restore to the engine oil and see if it slows down your oil consumption, also using a thicker weight oil will help. Depending on where you life and how cold it gets you might be able to use a straight 40 or even 50 weight engine oil. In hot Houston weather, we sometimes use straight 50 weight Castrol oil in our older cars with high mileage. If you live in snow country, 50 weight will be too thick, but talk to your mechanic and get his opinion.