TH350 OR 700R4

awdvkd · October 30, 2002

??? I have a 1987 chev 1/2 4X4 PU with a blow 700R4 do I gain anything by going with a th350 or th400 over the 700R4. Then can it be done and how trouble is it.

Kansas Kid · October 30, 2002

With either of them you would gain some strength and durability (much more with the TH400). But you are going to give up your overdrive gear. For me that is too big of a disadvantage to even think about swapping in the other two. A properly built (and cooled) 700R4 can be a very good transmission.....

MarkD · October 30, 2002

I would HIGHLY RECOMMEND keeping your overdrive tranny!!

SilveradoWV · October 30, 2002

I say keep a 700R4!

maggot · November 1, 2002

It all depends on what the man is wanting. I think the best of the three mentioned is the 400turbo. Man does that thing shift great. Very hard and right now. Plus I like this: with the 400T swap I did, I needed a bastard ujoint. Seriously that is what I had to get when I went from 350t in my old 70 Chevelle. I tore up 6 350T before I put in the 400T, it was the last tranny it had. It had 150K miles on it when I put it in in 1986, the car still runs today and has that same tranny in it and the car has been through few a teenage drivers. She is wore out and since the kid died who owned it it mainy sits, but evey now and than I see his dad drives it. It was cool, had a 307 with a huge thumper cam, 850 double pumper and my last rear end was, a get this, 271. It ran 16 in the 1/4 and would run 140+. At 80 I could yank it in 1 and stomp it and she just shat and gat.this was in the day, if a cop lost visual contact he could not ticket you, I drove these hillbilly cops nuts. whew sorry but seeing 400T took me back to my mis-spent youth.

95 Silverado · November 2, 2002

I agree, it depends on how you use the truck, local driving with any kind of hard use (plowing, towing etc.) go with the 400 turbo, the mid-eighties 3/4 ton trucks used 400/NP208 combo's, parts to swap shouldn't be that hard to find. On the other hand if you do a lot of highway driving, do the 700R-4 now, the money saved on the 400 will be spent on gas without the overdrive.

awdvkd · November 4, 2002

Thanks for the 2 cents, had the 700 tore down, looks like it was a fluid pressure problem. It looks like someone who rebuilt it last time didn't know what they were doing all the clutch packs were fried. Having it done right this time, can't wait to put it backl together. Again thanks for the feed back this place is very helpful.