4.3 700R4? *HRPC, looky*

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bucket

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I found out yesterday that a friend has a working 700R4 from an Astro van, with about 70K on it.. I know it will physically bolt in, but does the 700R4 have different internals for the V6's and V8's?

Also, I have a smoked 700r4 from my Camaro. Slips in forward gears, but reverse works fine. The TCI convertor in it cost nearly $400 and I'd like to get more use out of it. It should fine, shouldn't it?
 

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I found out yesterday that a friend has a working 700R4 from an Astro van, with about 70K on it.. I know it will physically bolt in, but does the 700R4 have different internals for the V6's and V8's?

Also, I have a smoked 700r4 from my Camaro. Slips in forward gears, but reverse works fine. The TCI convertor in it cost nearly $400 and I'd like to get more use out of it. It should fine, shouldn't it?
no, if you sjoked the trans, the converter is junk, unless you can find someone to cut it in half, clean all of the clutch material out of it, weld it back together straight and true, and balance it.

Skip cleaning it out, and you will have a new tool for destroying 700r4 internals on every trans you put it on.
 

HotRodPC

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The v6 vs v8 transmissions are generally the same with exception the v6 trans usually has 1 less clutch and steel in each of the clutch packs. The servo's apply a bit more pressure on the V8's too for more holding power. All of it's pretty easy to change out though. So if you have a v6 core you want to use, then use the clutch pistons and servo's from the v8 case.

I always recommend a new converter on a blown or burnt trans. The burnt clutch sludge goes thru the circuits and into the converter where it's then slung to the walls of the converter by centrifical force. Sure it will work, but how much junk is it going to allow back into the new trans making it shorter lived??? $400 for a converter? What kind of conveter is this??? Seems high in price. If it is a high stall or some fancy converter, then I'd get that one remanned for about $125-$150, or buy an OEM remann for about the same.
 

bucket

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Dammit, that sucks. I was hoping for a transmission that will hold up behind a mild 350 (if the gutless 305 ever blows). I don't want to upgrade it either, I may as well just have one of my cores rebuilt.

It was a higher stall TCI convertor, it stalled about 2300-2400 in my Camaro. I think it was $385 plus tax. I think it would be worth remanning it rather than just ditching it, I only got about 2000 miles of use out of it.
 

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Dammit, that sucks. I was hoping for a transmission that will hold up behind a mild 350 (if the gutless 305 ever blows). I don't want to upgrade it either, I may as well just have one of my cores rebuilt.

It was a higher stall TCI convertor, it stalled about 2300-2400 in my Camaro. I think it was $385 plus tax. I think it would be worth remanning it rather than just ditching it, I only got about 2000 miles of use out of it.

If it's only got 2K miles on it, depending on how bad it burnt, some converter shops can do a flush on it for about $30-$40 on it. That should get about 80-90% of the **** out of it. And you can hope the crap that is packed to the walls that didn't come out in a flush will stay stuck to the walls, and with centrifical force, never be allowed to enter the trans. And, if you're putting that trans behind a gutless 305, I'd run that v6 trans behind the gutless 305. Think of a gutless 305 compared to a modern v6 these days. Chances are the v6 might have had more guts than the Wee O Five. If you're just patching something up, I'd run it. When you step up the mild 350, plan on building a trans too, but for now, run that v6 trans behind the 305. Rock with it.
And yes, I'd hold onto that converter. When you want to use it on something new, I'd have that one remanned. It should have the good bearings, stator assembly, and be furnace brazed impeller etc. So all a reman will do is cut it, clean it, new bearings, new lock up clutch, reweld it, balance it and that's it.
 

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I don't know how bad it burnt. I had to slow down on the freeway one time, then when I sped back up, the 3-4 shift seemed a bit odd. When I got off the freeway 15 miles later, it failed when I hit the gas. It just slipped/shuddered badly (in all gears), but still could go through all the gears. Reverse worked fine. When I pulled the tranny, I drained all the fluid I could out the tailhousing. It was dark and stank.

I really don't want a V6 tranny if it's weaker. The 305 is old... it could die tomorrow and then a 350 would get tossed in so I can drive the truck to work. I don't want to drive carefully so I don't hurt the fragile tranny.
 

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Just go to a trans shop and see if they will sell you a corvette servo assembly and install a shift kit. It'll hold up. Then you can use the burnt trans out of your camaro to build it up good and put it in if the other ever goes out.

I used all the internals out of my 4L60E from my 95 4.3 Blazer to rebuild the 4L60E in my 2002 Silverado. Already had the vette servo in the 4.3 trans. Only thing I changed was I took out the upside down extra piston I had in the 1-2 accumulator and put the spring back in it. Trans worked till I got rid of the truck no problems.
 
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