700r4 Vs T400

[78304CJ-7]

Is the 700r4 as strong as the T400, I was under the impression the 700r4 was the replacement for the T400. The reason I am asking is I know a guy who does Militart Surpluss stuff and he has about 18 CUCV's (D60/14bolt) They have a 6.2 litlre diesel in them mated to a t400/Np208, they are locked in the back with LS in the front, 4.56 gears all around. All thise is stock, I am thinking of buying one as a tow/hauler but my concern is they only do about 60 with the diesel, instead of regaearing them I was thinking of putting in an OD auto, so I got to thinking 700r4..... will it hold up???

Specs on engine are:

135 at 3,600 RPM

They are not turbo but man I can get them with like 20k on them for decent money.....

Thoughts?

-RJ

[jerry]

I don't believe the overdrive will help that much I have 2 62 one with 3.73 stock and one with 4.11 the 3.73 are much better going on the freeway.
the one with 4.11 has 35 on it also it is still gear to low.

Jerry

[78304CJ-7]

I don't believe the overdrive will help that much I have 2 62 one with 3.73 stock and one with 4.11 the 3.73 are much better going on the freeway.
the one with 4.11 has 35 on it also it is still gear to low.

Jerry

I haven't done the cacs to see what my RPM will be, they have pretty small tires on there, 265x75xr16 or something like that. Anything will help I would reather not regear as 4.56 is the carrier break for the 60 so I would need a new locker too.... more money then the thing is worth hole to me....

Hmmmm

thanks for the imput

[shagg]

i have a 6.2 700r4 in my suburban never had any prob with it , but i was told that the 700r4 used behind diesels were built up inside to handle the high tq at low rpm`s by allison a branch of gm , how i found out was i found a great deal on a wrecked gas 700r4 with low miles i was going to get it for a spare the gm mech told me they were different inside too not just the tq converter so i passed on it hope that helps some

[jeepsr4ever]

20 of them, hey how much are they, maybe i could pick one up for parts!!

[281 quadcam]

it is my understanding the 700r4 was based on a TH350. However it is stronger than the TH350 and with lockup. sorry thats all i know.

[Dave Tickenoff]

The 700R4 was the replacement for the TH350 it is essentially a TH350 with an overdrive. Early production models had a few problems and failures were common, the failures were not HP related. If you are looking for a salvaged 700R4 get the latest model you can as they did see updates as production years went by. If you have someone build one or build one yourself talk with someone who knows them well there are parts to make them live with high HP and high RPM.

Dave

[Tigger]

Anything will help I would reather not regear as 4.56 is the carrier break for the 60 so I would need a new locker too

You can get a "Thick" 4.56 gearset for the D60 that is designed so you can use the 4.10 and down case.

[jeepsr4ever]

I like that option, rather than toss my powerlock sets i can regear them

[Toy Maker]

Anything will help I would reather not regear as 4.56 is the carrier break for the 60 so I would need a new locker too

You can get a "Thick" 4.56 gearset for the D60 that is designed so you can use the 4.10 and down case.

He already has the 4:56 gears so the only choice is to replace the carrier. Few of the CUCV's had front lockers, mostly in the Ambulance Spec. units, unless swapped in. If the front end has the locker, it is a Trac-Lock, which the bare carrier can be changed with the guts interchanged.
However, the rear 14bolt also has a ratio break so the rear carrier case would have to be changed to the 4:10 and down as well. Likewise the locker, a No-Spin can be interchanged between the cases.
The 700-R4 is based on the TH350. In a light weight (1/2 ton) 2X4 DD not used for heavy work, the 700 is great if built properly. For heavy usage, the 4L80E is the heavy duty version based on the TH400, and can be retrofitted with electronic controls available from Jet Performance. The 4L80E is a strong, reliable hard working unit.