average life span of 3.1 and 3.4 1999 and newer

[kustombuilder]

shopping for a car and have been looking at several Monte Carlos and Luminas from about 1999 on up. wondering about the dependability of these motors (3.1 and 3.4). i know about the intake leaks as i've read that information EVERWHERE so far in my search. i understand it's an inexpensive fix that takes about an hour???
my main question is what is the expected life span if these motors if properly maintained? i expect the usual stuff to go bad here and there (alternators, water pumps etc.) but what about the engine itself??
any other "issues" typical of these motors???


thanks so much folks.

Mike

[bszopi]

The intake gasket fix will take more than an hour, especially if you've never messed with this engine much. But don't take that as its a difficult procedure, as its not.

As far as lifespans go, there are several members on here that have engines well into the 200,000 miles and are still going with basically no problems.

[SappySE107]

Put the brown high temp o ring on the oil pump drive (where a distributor would normally go) and the metal LIM gaskets. Then with normal maintenance you should last 150k+.

[kustombuilder]

is this advice the same for either the 3.1 or the 3.4?? how about the 3.8? any difference or same proceedure??

thanks alot guys. glad i found this site.


Mike

[SappySE107]

3100 and 3400 are basicaly the same motor, just different bore. 99 3100 is small port actually so I wouldn't get that. 2000+ they are the same minus bore. 3800 is totally different and I couldn't tell you what they do.

[IsaacHayes]

1994 3100 here with 200k. If maintained and intake leaks caught and not left to destroy the motor, it should outlast the transmission.

[tractorman]

I don't want you to get the wrong impression about that intake job, Kustom. It's a BIG job. It'll cost something in the neighborhood of $600-$800 to have it done at the shop. I've done this job on three different engines- took me 5-6 hours each time, taking my time. Could've done it quicker if I'd been hurried, but I think most shops charge about that much labor time for the job. There are new and improved gaskets from both GM and Felpro that SHOULD make this a one-time repair.

Other than the lower intake gasket issue, these are good engines. I own two 3100's- one with 170k and one with 153k. Lots of people have run them well over 200k miles, and I expect that to be no problem at all with my '94 Corsica or my '01 Lumina.

[tractorman]

BTW- somebody here said that changing the LIM gasket on this engine is not a 'difficult' procedure... and I have some reservations about that claim. That's true if you're a professional mechanic or a VERY competent doityerselfer... but BEWARE. Lots of people (including MANY who've posted here after the fact) have seriously damaged their engines by screwing up this job. This isn't rocket surgery... but it's WAY beyond replacing an alternator.

You'll want to get somebody with experience to do the job unless you're pretty confident in your mechanical abilities. If the latter is the case, seek advice before tearing things apart. Lots of people here can walk you through it.

[86euro]

My dad bought a 3400 minivan new in '98. Sold it in '05 with 250+ on it and had NO troubles whatsoever. All the common things- intake gaskets, water pump, AC compressor, etc. were the originals and never needed replaced. Just oil changes and maybe plugs/wires. The thing even still had the original Dexcool in it.