3.4 GM Known issues?

Hey Guys, we just took in a nice trade that I am thinking about picking up for myself. I currently have a 1998 Buick Lesabre with 120,000 on the clock and it is an OK car. Everything works, but it has some issues (trans has a small issue, HVAC has a small issue, could use brakes soon, tie rods at some point, tires in 10-15,000 miles, etc)… Nothing major, but she is getting old… Now I only drive around 8-10,000 miles a year at this point (purchased the car in July of 2010 and have only put 12,000 on her)… So I figire this car will last a long time unless something changes.

Any way back to the trade its a 2002 Montana mini van, one owner van, well serviced (have most of its history), trans was replaced a little while ago. Its a fully loaded van, BUT it has 150,000 mile on it. It seems to run and drive great, and everything seems to work. So my question is, I have always looked at the 3.4 V6 as a crap motor… Am I worng?? I thought it was prone to head gaskets and the like, but I have recently seen a bunch with high miles on them (co worker has a Venture van with 180,000 same motor). I know the 3.8 in my lesaber is next to bulit proof, what are your guys thoughs on the 3.4??..

I figure what I can sell the Buick for will come very close to washing out what the Montana will cost me, which is why I am thinking about switching out. PLUS I have 2 kids, and like the idea of a second mini-van in the family (my wife already has one).


The only common issues I have seen is lower intake gaskets (very common, typically $700-800 to have a shop change them out and not too difficult for a reasonably mechanically inclined person to do on their own. Just be sure to keep the pushrods in order) and an occasional stopped up fuel injector. Fuel injectors seem to be more common on the older ones, and in that era, almost as common on the 3.8L engines. Other than that, anything else that can be said negatively of the 3.4L will also apply to the 3.8L. They are almost equal, in my opinion, with a slight edge going to the 3.8L. I wouldn’t call either engine junk.

I own a 2000 Silhouette which is the same van. I bought it at about 100K on it with all of its service records & things were done on it according to schedule. Its lower intake manifold gaskets were done twice - once under warranty by GM & the second time about 10K before I bought it. They’re leaking again, though thankfully not internally.

I’ve had it about 3yrs and have put about 60K on it. But it hasn’t been an easy, carefree time. Its the biggest piece of crap I’ve ever owned and requires near constant tinkering. And…when you try to tinker with it, it is practically impossible to work on. The only thing that’s kept me from dumping it is that I don’t have any money to do anything else.

Don’t assume that all will be well with transmission either (4T65E). Some of them are fine forever and ever. Some of them are just chronically a mess, and no one seems to know what to do with the mess. The one in my van was replaced at 55K under GM warranty. This was one of the reasons I bought it - tranny with only 50K on it. Well, it started having issues by about 110K. When I brought it to what is supposed to be my best local transmission shop the guy there said he stopped trying to rebuild them, and he doesn’t even try anymore - just orders a reman for it so at least the failures are someone else’s problem.

AFAIK the GM 3.4L has a very good rep - aside from the LIM gasket issues. But what is built around it - to me - is a major reason GM had to be bailed out. Crap. I wouldn’t recommend this van.

You will find those who have had opposite experiences.

A friend of mine has a 2001 Montana van and he has had to replace the lower intake manifold gaskets twice since he bought it new. Frankly, with other good choices available I wouldn’t bother with it unless you don’t mind doing the intake manifold gasket job from time to time.

Had a '96 Chevy Lumina APV, same as Montana. It had a V6 and I’ll just assume it was a 3.4L. It was a good running motor, no real issues. It got very good mpg for a minivan. The van stayed in the family, daughter bought it, and had just under 200K miles when traded in. There were more issues with hardware; latches, locks, power windows, and front suspension. Motor and trans were solid.

Null point now as they retailed the van yesterday. All well maybe next time.

I feel bad for the person who bought it. If they are not car saavy it will likely become a money pit.

I think you are better off keeping the Le Sabre.