700R4 Lock Up Converter Talk and Diagnose

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89Suburban

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I would love to get a core and take it apart and learn all this stuff. Someday I will.
 

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What number in that diagram is the sprag thing you 2 guys were talking about a few posts back?

#658 where it says Forward Sprag is an example of a sprag. And that is a true sprag.
Here's a pic of a Turbo 400 difference. Same part, but 2 different styles. One is a roller clutch, notice the rollers, and one is a sprag, notice the dogbone shaped wedges Those wedges don't spin or roll. They slip one direction and bind up in the other, why it's aka one way sprag and the roller clutch works the same way. It rolls one way, but locks up in the other.
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HotRodPC

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That pic above is of a Turbo 400 Low/Reverse Roller Clutch or One Way Sprag. This pic is of the intermediate Roller Clutch or Sprag which is needed for 2nd gear on a Turbo 400. Again, same part, just a different style. The true sprag is always going to be stronger. It has more holding strength and less likely to slip.

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89Suburban

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Ok, like a one way roller bearing in a pull starter. So what does this part do in 3rd and OD? And what does manually shifting to 3rd or OD do to save it?
 

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Ok, like a one way roller bearing in a pull starter. So what does this part do in 3rd and OD? And what does manually shifting to 3rd or OD do to save it?

I'd have to look to see what it's doing in 3rd and OD, I think that is the Forward clutch pack rides on that sprag. Won't swear to it, it's been awhile. Shifting to 3rd saves the 3/4 clutch pack by taking some of the strain off the clutch pack. Again, back to the 10 speed bike. The clutches only get compressed so tight by the apply piston to the pressure plate using fluid pressure. There is only so much fluid pressure, only so much clutch surface, and can only be compressed so tight. If with more strain, the pack can't hold tight, then it's going to slip. Using 3rd takes the strain off, as does a lower gear in the rear end.

Here is a top view or a roller clutch that slipped when it shouldn't have. You see the result. Now that outer race that has teeth on it, that's where the intermediate clutch ride. So what happened to this trans, as that roller clutch came apart, it locked up in both direction and couldn't spin free one direction and hold tight in the other. So now the trans goes into 3rd gear, but yet it's still got a clutch pack holding that shouldn't be, kinda like trying to be in 2 gears at the same time, and it cooked this bitch to no end. This was the trans that came out of the 84C20 that was bad when I bought the truck for $100. The guy was towing a tandelm axle enclosed trailer loaded to hell, and the bed of the truck loaded to hell and was driving from Little Rock, AR to Abilene, TX on a trans that had over 150,000 miles on it, and with 3.21 ***** gears. Cooked it !! Light's out, all done !!! He did make it within 5 or 6 miles of his destination though.

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Here is the intermediate clutches and steels that were riding on that intermediate race. A bit toasty !!!
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89Suburban

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Let me put it this way. Does it hurt the trans to tow in 3rd with shifter in OD compared to towing in 3rd with the shifter in 3rd?
 

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Check this out.
http://www.ebay.com/itm/Turbo-400-L...r_Truck_Parts_Accessories&hash=item20ccc8e158
This drum is very very rare. Only comes in 64 and 65 Turbo 400's. I've aquired like 5 of them. 3 of them I had machined to use a roller bearing instead of a thrust washer. I've sold one of the ones that wasn't machined for $125. This is for sale now. I'll go for $140 on the ones I had machined out with a lathe for the roller bearing. The roller bearing will take less hp robbing from the motor and smoother operation to the trans instead of friction on a thrust washer. These are what I use in transmision that launch off of NOS and a trans brake at about 1000-1200 hp and they hold up great. Talking like 8 and 9 second race cars.
 

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Let me put it this way. Does it hurt the trans to tow in 3rd with shifter in OD compared to towing in 3rd with the shifter in 3rd?

NO, now I see what you're getting at. As long as it's not in OD, your good to go. So if you're in OD but not going fast enough to call up for OD, and it stays in 3rd, then it's all good. Just stay out of OD to keep the strain off that clutch pack is all you're wanting to accomplish.

I'll let you in a little secret. When I build my 700r4, I'll be towing what the fugg I want to, and I'll be suing OD and I'll be doing 80mph doing it and not sweat a bit. BUT, I'll be the one building the transmission with a few extra goodies. This being one of them.

http://www.sonnax.com/product-lines/high-performance-transmission/parts/2010
 

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Here's the rest of those parts I was looking for:

http://www.sonnax.com/product-lines/high-performance-transmission/parts/3088

http://www.sonnax.com/product-lines/high-performance-transmission/parts/1338

http://www.sonnax.com/product-lines/high-performance-transmission/parts/3431

http://www.sonnax.com/product-lines/high-performance-transmission/parts/2012

http://www.sonnax.com/product-lines/high-performance-transmission/parts/1935

http://www.sonnax.com/product-lines/high-performance-transmission/parts/3096

And I'm still not finding the Sonnax release springs but I have a pic.

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NOw you why I haven't built it yet. Gonna take some funds, but the bitch will take some abuse and I have all of intentions of trying to tear it up. I'm going to flat ass abuse the hell out of the thing. Tear it up, find out what failed and back to the drawing board. Also why I might even go with a NP205.
 

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I got to get me a core to tear apart, this is killing me.
 

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You see all that aftermarket **** I intend to put in a 700r4? That **** will cost me close to $700, maybe even $800. But, with the torque converter I'll get from Edge converters out of California, it would be about a $3000 transmisison and should handle 600hp and 6500 rpm just fine and tow what I want with 3.73 or 4.10 gears in OD with a trans cooler.

I can build the same damn Th350 with about equal strength for about $200-$225.
 

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Right there's the baby. 1990 K case 700r4 just begging to be built at the end of that table.

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And if I break that case, then I have this 87 K case as a back up, and I'll build that ****** and blow it to smitherines too. Cores are cheap and most of those parts I listed, can go from one trans to another. Alot of those parts aren't wear type parts. Can't be to afraid to play hard and if you are, then you need to sit on the porch and watch. That's always been my motto, and I"m not going down any different either.

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HotRodPC

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I got to get me a core to tear apart, this is killing me.

Killing you? I have cores out my ass and can't do **** with them. Now that's fuggin frustrating. I have a damn A833 I can't play with either. Fuggin BS.
 

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Killing you? I have cores out my ass and can't do **** with them. Now that's fuggin frustrating. I have a damn A833 I can't play with either. Fuggin BS.

Just to learn the workings on it so when I am driving I know what parts are doing what as it shifts. I did a couple of old 727's back in my Dodge days so I have dabbled in auto trans before, that was a long time ago though and they were a pretty simple trans work on.
 

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