will a 700r4 replace a 400 turbo without to much drama

[stlbob]

I ask this because my beast sits right now because my trans has had it..weird too most times a GM will let you know its failing before it just FAILS..not this time..lost third gear driving to Walgreens.

A very close friend of mine has a trans shop he deals with whenever he gets trans issues or repairs thru his shop.Well he put me in contact with the guy and come to find out we had never bumped into each other but we know a lot of the same people in the industry here.

He told me he has a fresh 700r4 sitting on the shelf that he advises me to put in since im on 33's and have 4.10's..now i asked about the TC and the cross member issue he just said it is an easy swap..He is making a good ol' boy deal everyone else wanted 1600 to r&r my 400 turbo..this guy told me he would take my 400 as a core and give my the parts in the 700r4 at cost just pay him 100 bucks an hour which all told is about 900 bucks..he said maybe less if it goes quicker...NOW not to look a gift horse in the mouth..im of the school if it sounds to good to be true..etc,etc.OH yes just for grins i called AAMCO back and asked how much to flip it to a 700r4...2699-yeah you read that right.

Trying to find anyone on here that has done the swap,or helped to do the swap...just someone with some first hand experience..

 

[Honky Kong jr]

I ask this because my beast sits right now because my trans has had it..weird too most times a GM will let you know its failing before it just FAILS..not this time..lost third gear driving to Walgreens.

A very close friend of mine has a trans shop he deals with whenever he gets trans issues or repairs thru his shop.Well he put me in contact with the guy and come to find out we had never bumped into each other but we know a lot of the same people in the industry here.

He told me he has a fresh 700r4 sitting on the shelf that he advises me to put in since im on 33's and have 4.10's..now i asked about the TC and the cross member issue he just said it is an easy swap..He is making a good ol' boy deal everyone else wanted 1600 to r&r my 400 turbo..this guy told me he would take my 400 as a core and give my the parts in the 700r4 at cost just pay him 100 bucks an hour which all told is about 900 bucks..he said maybe less if it goes quicker...NOW not to look a gift horse in the mouth..im of the school if it sounds to good to be true..etc,etc.OH yes just for grins i called AAMCO back and asked how much to flip it to a 700r4...2699-yeah you read that right.

Trying to find anyone on here that has done the swap,or helped to do the swap...just someone with some first hand experience..

Not sure why you would put a 700r inplace of a 400? The 400 is way stronger. Did you get a price to rebuild the 400? I wouldn't do the swap especially in a 1 ton burb with a 454.

 

[CSFJ]

Yeah, I'm kinda on the same page as this. 4 digits to rebuild a three speed trans seems really excessive.

 

[Camar068]

700r4 is 27 spline count where as the 400 is 32, so you'll have to modify or get a different transfer case.

Agree with the guys above, stick with the th400. Is a 4l80 an option for him? That'll give him the 4th gear he may be looking for.

 

[74 Shortbed]

No frikkin way I'd put a 700 in a 1 ton burb with a big block, I'd build the 400 and put a GearVendor in if you want overdrive, that 6 speed is awesome..

 

[1987 GMC Jimmy]

Ooh, a gear vendor. Yeah, everyone's right. The later model, well built 700R4 is a beautiful work of art in RWD cars, half ton trucks, and even some 3/4 tons, but you shouldn't put it in a one tonner with a BBC. You should stick with the TH400. If you've got your mind set on overdrive, then a 4L80E with a standalone controller would be the nicest way to go.

 

[stlbob]

good im not crazy.He did say he had a 4L80 that needed to be gone thru.I miss being in a shop i would have already dealt with this.I have rebuilt a lot of PG 350 and a few T400's.Doing a 4wd trans on the ground just doesnt work for me.

I know the t400 is a great deal stronger.