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capev86 · 07-10-2009, 11:03 PM

you could beef up a 2004-R to replace that 400 and it would be a bolt in overdrive replacement. if you wanted to run a 700-R4, 4L80E or allison 5 or 6spd auto, you'd have to get more drastic with a custom length driveshaft! there is also the aftermarket aux overdrive route, but you still have to cut the shaft or get a custom one.

07-10-2009, 11:03 PM	#8
capev86 Registered User Join Date: May 2009 Location: Eliot, Maine Posts: 1,314	Re: What gear to use with the 402/th400?? you could beef up a 2004-R to replace that 400 and it would be a bolt in overdrive replacement. if you wanted to run a 700-R4, 4L80E or allison 5 or 6spd auto, you'd have to get more drastic with a custom length driveshaft! there is also the aftermarket aux overdrive route, but you still have to cut the shaft or get a custom one.