Swapping 3.4 for 3.1

[kennyrhit]

I have a 99 3.4L alero. I too had the header/manifold gasket leak. Unfortuately I found out about it after it overheated and ruined my engine. So I have to replace it and I was wondering if anyone knew what mods I need to make to put in a 3.1 in its place. What do I need to change?

[biv343]

At a minimum, you'd have to replace the ECM and wiring harness - I don't think those are interchangable between a 3.4 and 3.1. The trans should bolt up without any problem, but I believe that the motor mounts are different also.

Might be better off finding a boneyard 3.4 and go that route - it will save you a lot of time and grief.

[JTrujillo86]

DO NOT GO TO THE 3.1L V6. I had that motor in my 1997 Malibu and it was a huge piece of crap. The 3.4's, athough similar to the 3.1's, are much more reliable than the 3.1's.

Jeremy

[vamc]

FYI: a new 3.4L engine is about 2500-$3,000 for a new one. if you love it alot and want to keep it a long time, a new one might be the way to go, plus it will be under worrenty.

[cficare68]

Originally Posted by JTrujillo86

DO NOT GO TO THE 3.1L V6. I had that motor in my 1997 Malibu and it was a huge piece of crap. The 3.4's, athough similar to the 3.1's, are much more reliable than the 3.1's.

Jeremy

3.4 are not that reliable either. I had one in a 1999 Grand AM GT and overall with in the 2 years of owning it i put well over $5,000 in repairs to mainly because everything dealing with the radiator went bad, the computer went bad, i would own another car with a 3.4 in it if my life depending on it

[LeBuick]

Originally Posted by cficare68

3.4 are not that reliable either. I had one in a 1999 Grand AM GT and ... everything dealing with the radiator went bad, the computer went bad, i would own another car with a 3.4 in it if my life depending on it

But the motor ran well...

[jamcllw]

I think the 60 degree V6s from GM are probably some of the best engines they've ever built with the exception of the lower intake manifold gasket problems. I've personally owned 3 of them and each were around 250,000 miles when I sold them and they were still running strong.