700R4 to th400 tranny swap?
mudrunner80
06-18-2010, 12:45 PM
My transfer case has the front drive shaft on the left side (drivers side) NOT the right so I chose to just swap the input shaft. My question is,
Will my tranny bolt up to a 400 or do I need an adapter? Do they even make one? I don't even know which transfer case I have. When I mention my drive shaft is on the left side eye brows rise.
I looked over mine as good as I can but cant find numbers. It came bolted to the tranny 700R4. Any help would be greatly appreciated!
I forgot to mention, I have an 88 scottsdale IFS front end. Thought I'd add that in case
Don
Will my tranny bolt up to a 400 or do I need an adapter? Do they even make one? I don't even know which transfer case I have. When I mention my drive shaft is on the left side eye brows rise.
I looked over mine as good as I can but cant find numbers. It came bolted to the tranny 700R4. Any help would be greatly appreciated!
I forgot to mention, I have an 88 scottsdale IFS front end. Thought I'd add that in case
Don
mudrunner80
06-20-2010, 10:19 AM
Also, I never noticed till it was too late that I never got the dip stick with that th400 tranny. My question is, Will the dip stick from my 700R4 fit into the th400?
tblake
06-21-2010, 11:00 AM
I dont think the swap would be a good idea. You are going to have all sorts of issues along the way. Not to mention, wont you lose overdrive going from a 700r4 to a th400? With the gas money you lose running without overdrive, you could probably afford to have the 700r4 rebuilt every few years. If you find a repair shop that specializes in GM tranny's, they should be able to rebuild your 700r4 and it should last quite a while.
mudrunner80
06-21-2010, 11:48 AM
I dont think the swap would be a good idea. You are going to have all sorts of issues along the way. Not to mention, wont you lose overdrive going from a 700r4 to a th400? With the gas money you lose running without overdrive, you could probably afford to have the 700r4 rebuilt every few years. If you find a repair shop that specializes in GM tranny's, they should be able to rebuild your 700r4 and it should last quite a while.
No matter what I do to the 700R4 it wont ever be strong enough to haul a mud truck! THATS why I went to a th400. I'm not gonna support my local transmission repair shops every weekend. Thats just foolish! Its not like I'll be hauling the truck long distance. I can go without O/D if it saves on blown trannys on the side of the road with tow fees. So NO rebuilding a junk tranny is not a possibility!
No matter what I do to the 700R4 it wont ever be strong enough to haul a mud truck! THATS why I went to a th400. I'm not gonna support my local transmission repair shops every weekend. Thats just foolish! Its not like I'll be hauling the truck long distance. I can go without O/D if it saves on blown trannys on the side of the road with tow fees. So NO rebuilding a junk tranny is not a possibility!
tblake
06-22-2010, 11:39 AM
I was just sayin'.
Its going to be a lot of headaches swapping in something that wasn't meant to be. I doubt youl'd be rebuilding your trans every weekend. It came out of an 88. If its the original trans it did a damn good job. Hell, if its the second trans I'd consider myself lucky. I just don't want you to get the swap all done and then have so many issues with it that you end up having to swap the 700r4 back in.
BTW, you could tow your mud truck in "drive" and not "OD" with your 700r4 to save on the overdrive/reverse clutch pack splines.
Its going to be a lot of headaches swapping in something that wasn't meant to be. I doubt youl'd be rebuilding your trans every weekend. It came out of an 88. If its the original trans it did a damn good job. Hell, if its the second trans I'd consider myself lucky. I just don't want you to get the swap all done and then have so many issues with it that you end up having to swap the 700r4 back in.
BTW, you could tow your mud truck in "drive" and not "OD" with your 700r4 to save on the overdrive/reverse clutch pack splines.
mudrunner80
06-23-2010, 04:28 PM
I was just sayin'.
Its going to be a lot of headaches swapping in something that wasn't meant to be. I doubt youl'd be rebuilding your trans every weekend. It came out of an 88. If its the original trans it did a damn good job. Hell, if its the second trans I'd consider myself lucky. I just don't want you to get the swap all done and then have so many issues with it that you end up having to swap the 700r4 back in.
BTW, you could tow your mud truck in "drive" and not "OD" with your 700r4 to save on the overdrive/reverse clutch pack splines.
How do you figure? All I need to do is swap the input shaft in the tranny. I found out the tranny will bolt up to my stock transfer case.
Like I said earlier, The 700R4 trannys are total junk and GM should never have placed them into a truck! I get the same advise from every tranny shop I called. Infact, I only had one even willing to rebuild it but strongly advised me against it then adding I'd be throwing $900 out the window.
The tranny in it now is NOT the original tranny. When I got the truck it had a th350 which was bad when I got it and researched and put a "stock" tranny in its place.
What issues are you referring to I'd have and have to put another 700R4 in?
I spoke with the original owner and he told me he put the th350 in because he lost 3rd and 2nd gear was going. The th350 went because a tranny line busted (gotta love calcium on Maine winter roads) while his wife was driving it and thought she could make it home.
This current 700R4 worked great until I thought my truck could haul just under a cord of fire wood. In drive NOT O/D I might add.
Its going to be a lot of headaches swapping in something that wasn't meant to be. I doubt youl'd be rebuilding your trans every weekend. It came out of an 88. If its the original trans it did a damn good job. Hell, if its the second trans I'd consider myself lucky. I just don't want you to get the swap all done and then have so many issues with it that you end up having to swap the 700r4 back in.
BTW, you could tow your mud truck in "drive" and not "OD" with your 700r4 to save on the overdrive/reverse clutch pack splines.
How do you figure? All I need to do is swap the input shaft in the tranny. I found out the tranny will bolt up to my stock transfer case.
Like I said earlier, The 700R4 trannys are total junk and GM should never have placed them into a truck! I get the same advise from every tranny shop I called. Infact, I only had one even willing to rebuild it but strongly advised me against it then adding I'd be throwing $900 out the window.
The tranny in it now is NOT the original tranny. When I got the truck it had a th350 which was bad when I got it and researched and put a "stock" tranny in its place.
What issues are you referring to I'd have and have to put another 700R4 in?
I spoke with the original owner and he told me he put the th350 in because he lost 3rd and 2nd gear was going. The th350 went because a tranny line busted (gotta love calcium on Maine winter roads) while his wife was driving it and thought she could make it home.
This current 700R4 worked great until I thought my truck could haul just under a cord of fire wood. In drive NOT O/D I might add.
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