Transmisson swap

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MrPink

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short answer is no, the "drop" of the transfercase is on the wrong side with the Square body one being passenger side, and the GMT400 being driver. The trans would work but wont function like OE as the original trans in 93-94 is a 4l60E which is an OD trans. The trans in the 85 will more than likely be a TH350, or a TH400 depending on engine. The rarity would be a 700R4 for that year which was uncommon.
 

Papa Smurf

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short answer is no, the "drop" of the transfercase is on the wrong side with the Square body one being passenger side, and the GMT400 being driver. The trans would work but wont function like OE as the original trans in 93-94 is a 4l60E which is an OD trans. The trans in the 85 will more than likely be a TH350, or a TH400 depending on engine. The rarity would be a 700R4 for that year which was uncommon.
Thanks for information
 

618 Syndicate

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short answer is no, the "drop" of the transfercase is on the wrong side with the Square body one being passenger side, and the GMT400 being driver. The trans would work but wont function like OE as the original trans in 93-94 is a 4l60E which is an OD trans. The trans in the 85 will more than likely be a TH350, or a TH400 depending on engine. The rarity would be a 700R4 for that year which was uncommon.
I had a 82 K5 with a 700R4 from the factory.
 

stutaeng

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Didn't the 4L60"E" appear in 1993? So a 93 4L60E is not compatible with a 700R4 (or TH400) from a 85, unless OP gets a standalone controller?

A TH400 will, in addition, have the different spline count.

The driver side transfer case of the square body should mount to either, right? Assuming it's the right unit...see below.

And OP mentioned "C/K" so I don't know that he knows the 4x4 vs 2wd output shafts of transmissions are different within each transmission?

I hope that makes sense.
 
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HotrodZ06

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Transmission would need a vacuum line and/or throttle valve cable and a switch to engage tcc if so equipped provided it's automatic. Transfer case would only work if you did a solid axle swap with Chevrolet/GMC solid front axle.
 

Schurkey

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Lots of trucks with the 700 in '85. I was in a dealership in early '85. The shop was swamped with trans rebuilds, mostly under warranty.

The 700 in '85 was a complete piece of crap. They'd fry behind V-6s in S10s, let alone a V-8 in a full-size truck. TOTAL junk. We considered a TH350 to be a substantial improvement in load capacity and reliability. Which is pretty sad. B&M and others offered kits to remove the '700 in favor of a 350; no-one could make a 700 live behind any vehicle with a real engine.

There were a series of TH700 upgrades from '84 to '87, '88 for sure. After that, they were only weak, not "fookin' hopeless". When rebuilt, it's possible to take the worst of those transmissions and add the upgraded parts that the later versions got; along with aftermarket improvements. But as-built, I would not trust an '85 even if it is better than an '82 or '83.
 

L31MaxExpress

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Lots of trucks with the 700 in '85. I was in a dealership in early '85. The shop was swamped with trans rebuilds, mostly under warranty.

The 700 in '85 was a complete piece of crap. They'd fry behind V-6s in S10s, let alone a V-8 in a full-size truck. TOTAL junk. We considered a TH350 to be a substantial improvement in load capacity and reliability. Which is pretty sad. B&M and others offered kits to remove the '700 in favor of a 350; no-one could make a 700 live behind any vehicle with a real engine.

There were a series of TH700 upgrades from '84 to '87, '88 for sure. After that, they were only weak, not "fookin' hopeless". When rebuilt, it's possible to take the worst of those transmissions and add the upgraded parts that the later versions got; along with aftermarket improvements. But as-built, I would not trust an '85 even if it is better than an '82 or '83.
I find that funny because the only 700r4 or 4L60E I have been around that made it 100,000 miles much less the 250,000 miles it went without being cracked open was that 10/82 built one. I put a cam, headers and a performer rpm intake on that 305 at 150K. At 200K put a 350 in it with a cam. That 10/82 built 700r4 made it to ~250K, 50K of that behind a 350 making more than 300 hp. That early 700r4 also hauled a camper behind that old G20 van all over the place in the early 90s. Mountains of New Mexico and Colorado and down to the coast numerous times. Was also no stranger to hauling the 24 ft pontoon boat around. My parents eould put it in Drive (Overdrive) because it was labeled D-3-2-1 and drive away. The 97 Express nuked the first 4L60E at 38K and that was never having towed anything. The 4L65E that replaced it went 40K. At 78K put an 85E in it and then put a hitch on it.
 
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