Getting my 700R4 rebuilt

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Bextreme04

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There's probably more K case 700r4s than non K case.

You'd have to go out of your way to find a non K case.

There's four of them on facebook marketplace in Portland right now for under $400. There are far more 87-later K case 4x4 transmissions on marketplace around me than any other kind. Arches and K clearly seen in all the pics. It was honestly much harder to find an early 700R4 and MUCH harder to find 2wd in my area when I was looking.
 

Vbb199

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I'm currently running a K case 700r4 in my 89 r1500 burb.
 

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There's four of them on facebook marketplace in Portland right now for under $400. There are far more 87-later K case 4x4 transmissions on marketplace around me than any other kind. Arches and K clearly seen in all the pics. It was honestly much harder to find an early 700R4 and MUCH harder to find 2wd in my area when I was looking.

This is what I'm talking about where it comes to the Puget sound area, and I'm not trying to sound like a a whinny little baby, it's just how it is here. FB market place. There is one transmission listed as a transmission for a chevy 350 no other information, but it looks like a 700. Owner has no idea what type, how many gears or what year and isn't inclined to look. He's 30 miles from me in Marysville. There's a $150 700 in Moses Lake the other side of the mountains... Haven't contact him, but no info about age. One in Seattle for $650, no age info. Have not contacted him. I see the ones in Portland, and that would be really nice if I was in or around Portland, but I'm unlikely to spend an entire day driving to Portland and back, hoping to come home with what I need.

CL: Nothing until I get to Portland or Eastern, Wa and you can forget about offer up around here.

I could try contacting John or Kenny in Sultan, but if he's got anything you know he's going to be charging top dollar.

Even the trans builder, is like any 700 is getting hard to find unless you leave the area...

With that said I will keep looking but do not hold out a lot of hope. Of course there are units on E-bay but shipping, just like gasoline and time to Portland kill the deal. I'm sure you guys have heard me bittch about the wrecking yard situation up here too. Another dead end.

There's probably more K case 700r4s than non K case.

You'd have to go out of your way to find a non K case.
Ok, good to know up until I started looking last night I've not looked for core 700's. Thanks.
 

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There's one transmission builder that I personally would recommend over others because they have such a massive reputation for building SEVERE duty transmissions in the mega mud truck (bigger than 44" tire) world.

Check out "king krush mega truck" sometime.
He sports patriot building.


Meaning, they know how to build them to reasonably last in the worst possible case.

Patriot Transmissions in Florida.


There's another member on this forum I recommended Patriot to. He's currently running their 700r4 in his truck right now to this date.
 

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Precision Transmissions in Texas also has quite a nice following in the HP world, and he's got his own youtube series thats extremely popular.

It's one of those "you can watch him build your transmission" things.

Everything I've watched from that guy seems spot on, and he'll, I've learned alot from him.
 

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I will try not to use the F word here, but I have a question. I just went through a trans replacement on my work vehicle. When I found a place to re manufacture my trans, part of their service was updating the trans with all the latest manufacture fixes and revisions to make it up to current specs.

Is this not something that can be done with the 700r4?
 

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I will try not to use the F word here, but I have a question. I just went through a trans replacement on my work vehicle. When I found a place to re manufacture my trans, part of their service was updating the trans with all the latest manufacture fixes and revisions to make it up to current specs.

Is this not something that can be done with the 700r4?
I think Vince or Matt can answer this better than I can, but my understanding from talking to the builder I'm planning to work with is the answer is yes sort of. The early transmissions can be updated a lot, but simply getting a core with the last factory updates is likely better possibly cheaper, though I'd argue that depends on where you live. The reason being is the later transmissions had an aux valve body and larger fluid passages. My understand is that stuff can be done but to an first generation, but how much do want to spend. The 27 spline shaft can be changed to a 30 I think, the builder talked a little bit about making modifications to do that. I know the rest of the stuff servos and clutch pack can be upgraded without an issue.

And as my builder pointed out it is hard to say what may already have been done inside my transmission until it's opened up. Maybe nothing, maybe something.
 

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I think Vince or Matt can answer this better than I can, but my understanding from talking to the builder I'm planning to work with is the answer is yes sort of. The early transmissions can be updated a lot, but simply getting a core with the last factory updates is likely better possibly cheaper, though I'd argue that depends on where you live. The reason being is the later transmissions had an aux valve body and larger fluid passages. My understand is that stuff can be done but to an first generation, but how much do want to spend. The 27 spline shaft can be changed to a 30 I think, the builder talked a little bit about making modifications to do that. I know the rest of the stuff servos and clutch pack can be upgraded without an issue.

And as my builder pointed out it is hard to say what may already have been done inside my transmission until it's opened up. Maybe nothing, maybe something.


^ the standard rebuild kits themselves typically have all the "to date" upgrades over the oem specs (sealing surfaces, washers, bushings, filters, springs, valves) even in a stock application. Most basic name brand "overhaul" kits cover all the inferior design flaws the factory unit had. I don't know what kit WOULD sell actual oem spec seals and the aforementioned unless it was rock bottom budget kit.
And I think you get the idea.... extra extra work to make a outdated unit work, or upgrade to the 87+ unit with the upgrades already there.

I also want to add, and i think it physically only applies to the tailshaft housing, but the 87-89 700r4 uses a cable driven speedo. The 90-91 is a vss speedometer



I have heard (haven't built one myself yet) a 91 700r4 is real pain to rebuild, suggesting it's different than the others.
 

SirRobyn0

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^ the standard rebuild kits themselves typically have all the "to date" upgrades over the oem specs (sealing surfaces, washers, bushings, filters, springs, valves) even in a stock application. Most basic name brand "overhaul" kits cover all the inferior design flaws the factory unit had. I don't know what kit WOULD sell actual oem spec seals and the aforementioned unless it was rock bottom budget kit.
And I think you get the idea.... extra extra work to make a outdated unit work, or upgrade to the 87+ unit with the upgrades already there.

I also want to add, and i think it physically only applies to the tailshaft housing, but the 87-89 700r4 uses a cable driven speedo. The 90-91 is a vss speedometer



I have heard (haven't built one myself yet) a 91 700r4 is real pain to rebuild, suggesting it's different than the others.
Thanks for that Vince. Though I'm not a tranny builder, I want to understand as best I can so I can make the right choices moving forward and really apricate everything you have shared so I can make good choices.
 

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