Topic: 4.3L swap need some advice

[crawler83]

Ok folks here is the scoop, I have a 93 chevy astro van with a 4.3L fuel injected v6 with a blown tranny. I got the van for the sole purpose of swapping the motor into my 83 P/U, the problem is that my truck comes with a L52 that can't be adapted to the chevy because of the one piece . After some research I decided that I wanted to go with the G54 tranny that has the lower first gear and the higher fifth gear, but the G54 tranny I heard cant be adapted to the gear driven t/case that I have stock because the t/case shifter is located in the tail shaft of the tranny, if this is true how would I adapt a dual case with that setup.

[BigMike]

Hey crawler83,

This is correct in that the G-series transmissions use a forward shift style transfercase where as the L-series use a top shift style transfercase. But you can still use a top shift style t/case with a G-series as long as you block the now empty shifter hole on the rear tailhousing (where the normal forward shifting shifter would be).

BUT!! I strongly suggest that you do NOT use a G-series transmission with a V6!! It is not the best choice in terms of strength. I would recommend using a W56 (1985-1988 EF), or the best choice, I would strongly recommend using a R151F (1986-1987 Turbo EFI) transmission.

I have heard of guys running G-trans behind Torque engines, but they never hold up for long.

Regards,
BigMike

[crawler83 [OP]]

Thanks mike,

I've been a big fan of your products for a long time and appreciate your advice. I think with this new found info it will make my conversion much easier to plan out and get completed.

Thanks, wade

[BigMike]

No problem wade,

Let us know how the conversion is going and include some pictures!

Regards,
BigMike

[mr4x42u]

could go with a gm auto and toy t-case,4;70 gear set..Cost wise may be the same and faster then finding an r151f...Just a thought..Yea,,slush box but better slush box them broken trans on the trail... :chug:
Just a thought....

[crawler83 [OP]]

Thanks for the info, I like to hear all the different opinions on this swap. The auto trans would be an easy swap just fo the fact that I wouldnt have to buy the advanced adapter kit, but I really would prefer the manual tranny over the auto. Not to mention the fact that I have already bought a w56 tranny and ordered the advanced adapter kit last week.

thanks again for the feed back,
cheers, wade