Thoughts on going to a 4spd overdrive?

Bextreme04

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That would surprise me. So where are they all now? You can still find 400s in every junk yard and farmers field. 700..s not so much.
They are in every single 1/2 ton pickup and van in the junkyard made after '87 and about half the ones made between 82-87. The rest have TH350's.... very occasionally you'll find a 4-spd manual. Around here I see probably 4:1 Manual 4-speeds to TH400 and you don't see many manuals.

I have NEVER seen a TH400 in any of the junkyards near me and rarely see them in any of the squares I see for sale either. Most of them have TH350 or 700R4's....
 

shiftpro

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They are in every single 1/2 ton pickup and van in the junkyard made after '87 and about half the ones made between 82-87. The rest have TH350's.... very occasionally you'll find a 4-spd manual. Around here I see probably 4:1 Manual 4-speeds to TH400 and you don't see many manuals.

I have NEVER seen a TH400 in any of the junkyards near me and rarely see them in any of the squares I see for sale either. Most of them have TH350 or 700R4's....

Yeah I get that, but I'm speaking from my experiences in my location. Here in BC it's hard to find old squares (especially the 70s) with any automatics. Go to Alberta and they were mad about 3/4 and 1 ton trucks... not so many 4x4s... and autos, which would be 400s. Further east to Saskatchewan there were many more 1/2 ton trucks with the 350.. up until the 80's when they were as you said, overdrives. Some places in the west the squares were scarce because there were pockets of Ford Country. No 350, 400, 700s to found out there! Regional microcosms of whatevers abound.
 

Matt69olds

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Every model year 83ish and later 1/2 truck, van, most rear wheel drive passenger cars, Camaro, Firebird, corvette, S-10 trucks/vans, B bodies, literally millions of cars. The 400 WAS pretty plentiful, the chevy 400 are getting really hard to find. The BOP 400 (especially the long shaft models) are pretty easy to find around here.

I’d be willing to bet the overall 700/4L60e production is probably 3-4 times the 400 production.
 
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Vbb199

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All i'll say here, is someone whos actually handled the internals of automatic transmissions, beaten on them and broken them because i can rebuild them, built them for a hotrod, friends, or offroad rigs , and tows with them in my square, and uses them daily in my square, and travels with them in my square (hours at a time), the 700r4 is the most no nonsense automatic to install in your truck for an all around use.
The nice low first of the 700r4 beats both the th400 and the 4L80e, and the only way to compensate for that lack of a low first gear is to have a low axle ratio, which ultimately affects your final drive (OD). Theres no two ways about it.
As said, if it was such a failure, why was millions of them made, and why are they still being built, sold, and ran, today?

The only thing a th400 is good for is for 2 things that most here dont even have, a bigass 4x4, or a hotass big block/diesel powered truck (or car)

If you fancy advanced electronics, and dont care about oem status in your squarebody, by all means, go a step up and install a 4L80e. But this level of general misinformation is wild.
 
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Vbb199

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They are in every single 1/2 ton pickup and van in the junkyard made after '87 and about half the ones made between 82-87. The rest have TH350's.... very occasionally you'll find a 4-spd manual. Around here I see probably 4:1 Manual 4-speeds to TH400 and you don't see many manuals.

I have NEVER seen a TH400 in any of the junkyards near me and rarely see them in any of the squares I see for sale either. Most of them have TH350 or 700R4's....


Sadly, th350s and th400 arent vanishing, if i find a good core, i buy it, sight unseen. The gamble of spending 1-200$ for a core thats potentially a rust bucket inside, and getting just *1* servicable OEM part from it was well worth the money.

Scrap the rest, save the case.
Ive got a nice little collection of automatic parts boxed and labeled away so i have them right on hand should i need them
 

SquareRoot

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I’m curious why you are so insistent 700/4L60E are junk? While you will get no argument from me they are definitely not the most durable trans, in the right application my experience has been pretty positive.
I'm with Rusty. 700's are junk.
Junk, junk, junk, junk,junk, junk. Get it? JUNK! Carry on.
 

John Nes

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Sadly, th350s and th400 arent vanishing, if i find a good core, i buy it, sight unseen. The gamble of spending 1-200$ for a core thats potentially a rust bucket inside, and getting just *1* servicable OEM part from it was well worth the money.

Scrap the rest, save the case.
Ive got a nice little collection of automatic parts boxed and labeled away so i have them right on hand should i need them
I picked up a known working th400 that had been sitting at the shop for a while for 200$ Just cuz.

Also after i first picked up my 87, I had the 700r4 rebuilt and the only issue I’ve had with it was the ratio output adapter didn’t have a great seal. Other than that I got no problems burying the needles and doin +90 combined with the 3.08 rear
 

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See?Junk.

Reader,
How long did GM make turbo 400s?
Compared to how long did they make 700s?
Which was used in more vehicles?
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Which do ya figure moves more vehicles - today?

Bros. Your knickers are in a ball - maybe you should have a Snickers first huh?
Yup. Knicker Twist. Wife gets it almost daily. And btw, 700's are junk!
 

SquareRoot

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That's a great point..ya know I bet you could build two or three turbo 400s for the cost of one of them p_ssy overdrives.

Let's get real (who am I kidding) how many gears do you think is necessary for the next run to macdonalds anyway? Savin gas are ya? Gonna save the planet better with your 4 inch lift and 35s or do ya think its best to stick with 2 inches and 32s?
Big block or bust.
Overdrive.
Gas mileage.
VORTEX HEDS BABY!
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fix.everything.
Vortec Rusty, vortec!
 

SquareRoot

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All i'll say here, is someone whos actually handled the internals of automatic transmissions, beaten on them and broken them because i can rebuild them, built them for a hotrod, friends, or offroad rigs , and tows with them in my square, and uses them daily in my square, and travels with them in my square (hours at a time), the 700r4 is the most no nonsense automatic to install in your truck for an all around use.
The nice low first of the 700r4 beats both the th400 and the 4L80e, and the only way to compensate for that lack of a low first gear is to have a low axle ratio, which ultimately affects your final drive (OD). Theres no two ways about it.
As said, if it was such a failure, why was millions of them made, and why are they still being built, sold, and ran, today?

The only thing a th400 is good for is for 2 things that most here dont even have, a bigass 4x4, or a hotass big block/diesel powered truck (or car)

If you fancy advanced electronics, and dont care about oem status in your squarebody, by all means, go a step up and install a 4L80e. But this level of general misinformation is wild.
700=Junk. In fact I don't know why I'm on the 700is junk bandwagon when what I really feel deep down inside is ALL automatic slushboxes are junk.
4 speed and proper gears or big boy pants and NV4500. Allison. That might tickle my fancy if auto was my only choice. Now, about that Hagertys 502 vbb?
 

Vbb199

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700=Junk. In fact I don't know why I'm on the 700is junk bandwagon when what I really feel deep down inside is ALL automatic slushboxes are junk.
4 speed and proper gears or big boy pants and NV4500. Allison. That might tickle my fancy if auto was my only choice. Now, about that Hagertys 502 vbb?

Burning tires
Its getting old lol
Until i have fatties, its not gonna quit
 

Green79Scottsdale

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I'm with Rusty. 700's are junk.
Junk, junk, junk, junk,junk, junk. Get it? JUNK! Carry on.

I am not necessarily arguing, but I can't take you serious if you don't give reasons. Just standing there proclaiming something without solid reasoning doesn't make people think critically.
 

SquareRoot

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I am not necessarily arguing, but I can't take you serious if you don't give reasons. Just standing there proclaiming something without solid reasoning doesn't make people think critically.
I'm just making noise. I like to get rusty and vbb riled up. I'm done now. Carry on.
 

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