V-6 engine/trans swaps

[McShank]

My '88 22re Sunrader might just run forever, however if the day comes when I have serious engine or trans problems I will want to swap in a V6 and matching trans. Twenty-five years ago I put a Capri V6 in a VW Camper and thought I had learned my lesson about changing stock set-ups, but I can't stop dreaming about getting more power in my Sunrader. There is a lot of info out there, much of it pertaining to 4X4 rock crawlers and the two most recommended choices are the Buick 3.8L with 700R4 auto trans or a GM Vortec 4.3L with 4L60E. I found good sources for complete pull outs with original wiring, alternators, ac compressors, computers, harnesses etc. Mounting hardware, headers and drop in radiators are available but there seem to be some clearance issues for oil pan, distributor and suspension travel, particularly with the 4.3, that require a lift kit or other modifiactions. I wonder if some of the problems would be found only in a 4X4 truck and not with a motorhome. I'm not looking to race it, just have great pulling power on hills and at high altitude so I don't incite road rage from those behind me. Has anyone out there done one of these? Any major pains doing the swap or unforseen issues? Did mpg go down or stay the same? Problems with Dept. of Motor Vehicles registration or emissions? I'd love to hear from anyone experienced with these swaps.

McShank

[futar]

There was a 4.3 conversion Toyhome for sale last year. I asked them and the said it was easy. They claimed around 16mpg. I wish I had kept the info as I dream of doing one. The 4.3 is perfect. It is a durable truck engine with the accent on torque. I have one in a 96 Astro. The later models are better. Mine has 160,000 miles, no oil burning, with no end in sight. And that's with trailer towing. It's not unusual to get 250,000 miles out of one.

The premier info people seem to be http://www.northwestoffroad.com/parts/engineadapters.html

[McShank]

futar;

Thanks for the input. Advance Adapters and Downey are two other companies that make hardware to do a swap like this. I found someone who specializes in Chevy S10 parts including complete pull outs with all the original computers, harnesses, etc. They listed a 2004 Vortec + trans with 60K miles on it for $1500 plus shipping a few weeks ago. One or two pull outs show up every week. I like the idea of not having to match up Toyota trans or computers with a GM engine, but I don't know if the problems with fitting it into the Toyota compartment have more to do with 4X4's. I do know swapping will always bring some unforseen problems to overcome. I don't get to use my Sunrader very often and might never have to decide to replace the 22RE but sometimes daydreams come true.

McShank

[keitholivier]

Just watch the front axle weight limit. The 4.3 vortec and 4L60 tranny is a pretty heavy combo although of course a 4L80 is even worse. It may be neccersary to add coil over shock stiffeners to the front suspension since there is nothing that can be done with the original torsion bar setup that I know of. That still leaves the original hubs and stub axles as weak points.

I have been considering a GM 3400 V6 which I think is a bit lighter than the 4.3 Vortec and at least not significantly heavier than the Toyota V6. The Vortec is a 90 degree V angle, so it may be wider than the 60 degree 3400 series engines.

Just a thought.