Crate 700r4 for $1500 or less?

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bucket

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That makes sense then, the tap I used was the one on the driver side. I never looked on the passenger side.
 

HotRodPC

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That makes sense then, the tap I used was the one on the driver side. I never looked on the passenger side.

Yep, fairly certian, even 4L60-E have the line pressure tap on the driver side about in the center of the trans.
 

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BTW, here is another tell tale sign of the good or better 700r4. Look for the rainbow shape sprue or flashing on the passenger side.

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Jims86

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The best way is to pull the pan and look for the aux valve body, and the 86 unit has a pressure tap on the right side behind the tv cable....or is it 2? i forget
 

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BTW, here is another tell tale sign of the good or better 700r4. Look for the rainbow shape sprue or flashing on the passenger side.

attachment.php

Good info! :waytogo:
 

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The best way is to pull the pan and look for the aux valve body, and the 86 unit has a pressure tap on the right side behind the tv cable....or is it 2? i forget

2 pressure taps near the TV cable on the passenger side. Also, the Aux VB started in some 87's. and why some 87's are good. Stay safe and get 88-92 units.
 

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But what does the aux valve body do? It seemed to me that it's only there for driver comfort. In stock form, I've killed just as many late 700r's as I have killed early ones.
 

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But what does the aux valve body do? It seemed to me that it's only there for driver comfort. In stock form, I've killed just as many late 700r's as I have killed early ones.

You are right, the biggest notice woud be smoother 2-1 downshifts, and shifting while parked going thru the gears so they are not so harsh. BUT, there is also an added whats called Abuse valve. It increases the speed of the forward clutch apply piston. This reduces heat and increases durability for the forward clutch pack. So really, it doesn't do moch. If you don't abuse an 82-86, then the 87 isn't much better other than smoother shifts which the benefit is not being harsh on other hard parts. The abuse valve only really helps if you are like rocking the truck if you are stuck. You'll get a quicker gear back and forth from forward to reverse, to forward etc etc making the trans able to tolerate that type of abuse better and why the valve got its name Abuse vavle. Accrording to ATSG anyway.
 
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:popcorn:
 

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Mine has a rough 2-1 downshift, but it's only really noticable when the OD is off. It doesn't seem to run through the gears harshly though. Would that likely be the good '87?
 

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Mine has a rough 2-1 downshift, but it's only really noticable when the OD is off. It doesn't seem to run through the gears harshly though. Would that likely be the good '87?

mine is an 88 K trans, And it downshifts pretty hard when in 3 speed range, upshifts pretty hard under WOT
 

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Mine has a rough 2-1 downshift, but it's only really noticable when the OD is off. It doesn't seem to run through the gears harshly though. Would that likely be the good '87?

Really hard to say dhamp. These alluminum valve bodies also tend to wear valve bores so if you have worn valve bores, that can change the charachteristics and attitude of your transmission also. If you want to know for sure what you have. Get the #'s off the passenger side, at the rear of the pan, and just above the pan on the case itself. The first digit of the # group will tell you what year your transmission is. I've posted pics on where to find the # in identifying the 700r4.
 

HotRodPC

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mine is an 88 K trans, And it downshifts pretty hard when in 3 speed range, upshifts pretty hard under WOT

That's one of the best 700r4's you can get. Not saying much since its still a 700r4 but still the best. Again, if your valve bores are wore, that can change the attitude of the transmission. Also, if someone has previously added a shift kit or installed Corvette Servos. That will also firm up 1-2 shift. If other servos were upgraded to be firmmer shifts then you'd likley notice that too. Very hard to know what's in a transmission if you're not the original owner or didn't build it yourself.
 

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