Originally Posted by smilanchi

I appreciate any advice regarding aftermarket engine mounts. My engine mounts need to be replaced. The part numbers are 15236456 (left) and 15925797 (right). I was told it's better to replace the transmission mount (p/n 15804744) at the same time. I can't find the GM/AcDelco 15925797 but I found the other two original parts. Is it better use the original left engine mount and transmission mount and an aftermarket right mount? Or is it better to use the same aftermarket brand for both engine mounts and transmission mount? Any recommendation on a reliable aftermarket mount? Any help is greatly appreciated.
Also does anyone know a good auto mechanic for Hummer H3 in Orange County, CA?
I have a Hummer H3 2007 with 185K miles. I recently bought this car and drive 500 miles a month, city miles only. No off roading.

Originally Posted by amrg

Agree with Doc Olds,

I have done an LS swap on my truck, it was an alpha so it was straight forward. The person that bought my engine complete with accessories swapped it into his I5, it was costly to him.

1. You need a complete wiring harness to plug into the V8 or you can modify your current harness. Depending on year, you may need a new PCM and you need to program it
2. Engine mount adapters to mount the V8 in place of the I5 (available)
3. Various parts (heater hoses, radiator hoses, air intake hoses, O2 sensors, vaccum hoses, fuel lines)
4. H3 specific parts that only work on the H3 to clear frame rails or differential (engine oil pan, H3 exhaust manifolds and y pipes)
5. Need to do transmission work to convert from a 4l60e that works on the I5 to a 4l60e that works on the V8 (bell housing, torque converter, input shaft and new stator shaft)
6. Accessory brackets that allow you to mount the alternator, ac compressor and power steering pump in the same config that fits the hummer h3 (esp between the frame rails below and to clear the fuse box up top)

Best thing to do is go to an alpha,
Second best thing is to get a complete engine with accessories and a transmission plus wiring harness and exhaust system (and make sure its compatible with your pcm year) from an Alpha otherwise add a pcm and tcm to the equation.

Originally Posted by Bouzobar

can the Alpha harness be used for an LS, is it a direct plug&play?