Tranny Swap??

[HotRod73]

I'm wanting to swap to a 700r4 with od. Now, my question is... will a 700r4 from a v6 work? will any 700r4 work?? what is needed to change from th350 to 700r? its going in my 87 swb with the 305 tbi...

[krue]

I'm not an expert on the 70's trucks, but the 700 should work in place of the th350 in your truck using the same driveshaft. All of the 700's will fit, but the ones off the little v-6's (2.8, 3.1) may not have the same bellhousing bolt pattern.

[rfmaster]

HotRod

About 4 month ago I swapped out TH350 for 700R4 in my '75 C20. It was a straight swap because original TH-350 had 9 inch tail shaft. Most Car TH-350 have 6 inch tail shaft. In my case the only mods that I had to do is to move and drill tranny cross member and getting TV cable right. I strong word of caution - go to Bow Tie Overdrives web site http://www.tvmadeez.com/ and read about TV cable set up. It is very important.

Regarding V6 700R4 - I would avoid it for several reasons. I also, would avoid all pre 87 700R4 as they use very weak internal parts. Starting 87 GM updated 700R4. Pre 87 700R4's can be updated to later specs, but expect to pay for hard parts. 700R4 is not as strong as TH-350 - it will not take massive abuse, however if you are looking for daily driver gas mileage improvement it is the way to go. Check out Mike Rowand web site http://www.rowand.net/Shop/Tech/Auto...issionSwap.htm
for detailed info which I used for my swap.

Good Luck
//RF

[HotRod73]

i just want the overdrive

[piecesparts]

I have installed a couple of 700R4s in the place of the TH350C trannies in my and my Son's mid eighties trucks. I have also abused the 700s and they will give what the 350 has and then some, everything has a limit. It is true STAY AWAY from the early 700s, they had problems. I since have had my trannies built up to take the HP that my stroker motor is capable of and what I do in my daily driver and they are doing just fine. I have logged a lot of miles on my trannies and I am satisfied.

[HotRod73]

yeah so i need one between 87- the last year before they made them electronic??? or wud i be better keping 350 and throwin a shift kit in it and have some fun?

[piecesparts]

The 700 will give you a much lower first gear than the 350, and it throws in the OD as a bonus. That in itself will give you a stronger start on take off and better gas mileage. The 700s have a difference in the TV cable thinking, rather than a "Kick down" that the 350 has, but it is not all that complicated. The lock-up converter can be triggered by a switch from many different sources and those are out there in the market, you would not need a computer. OR You can eleminate the lockup converter all together---your choice. If you purchase a 700, PUT shift kit i n it to wensure that it wi working smoth on installation.

[HotRod73]

do i need lockup? what is that?

[rfmaster]

HotRod

Lock up torque converter illuminates slippage that is otherwise always present in conventional torque converter. Conventional torque converter is fluid based coupler device between engine and transmission. It also provides high pressure hydraulic fluid for control purposes within tranny.
Lockup torque will result in better fuel economy because all converter slippage is eliminated when the converter locks. Also, tranny fluid temperature reduction at highway speeds.

In the early 90's GM renamed 700R4 into 4L60. The 4L60-E is the electronically shift controlled version of the 4L60. The 4L60-E was released in 1997 and fully phased into wide use through GM by 1998 along with its heavy duty brother 4L80-E. 4L60-E (and 4L80-E) requires external ECM to provide shift control. 700R4 and 4L60 do not require ECM for shift control, but require TV cable for shift quality and 4 pin connector for TCC control and indication.

//RF

[piecesparts]

Originally Posted by rfmaster

HotRod

Lock up torque converter illuminates slippage that is otherwise always present in conventional torque converter. Conventional torque converter is fluid based coupler device between engine and transmission. It also provides high pressure hydraulic fluid for control purposes within tranny.
Lockup torque will result in better fuel economy because all converter slippage is eliminated when the converter locks. Also, tranny fluid temperature reduction at highway speeds.

In the early 90's GM renamed 700R4 into 4L60. The 4L60-E is the electronically shift controlled version of the 4L60. The 4L60-E was released in 1997 and fully phased into wide use through GM by 1998 along with its heavy duty brother 4L80-E. 4L60-E (and 4L80-E) requires external ECM to provide shift control. 700R4 and 4L60 do not require ECM for shift control, but require TV cable for shift quality and 4 pin connector for TCC control and indication.

//RF

The statements above are true, however the 700s can be operated without the lock-up and the losses are there as stated. The 700R4 tranny can be set up to lock-up from it's own pressure system, or from an outside switching source.