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Help ID a 700-R4 or ?

1082 Views 1 Reply 2 Participants Last post by  Hoghead
I have a tranny that I believe to be a 700R4.

The overall length is real close to 31". The tail shaft housing is 7 1/4". The pan is square.

There is a tranny mount just in front of the tail shaft housing. The numbers on the tranny housing just above the rear of the tranny fluid pan on the pass side are:

Anybody have a decoding ring that will translate this? I got as far as the year; 1984.

Sure would appreciate the rest of the info, especially the vehicle it was on.

Lastly, the search engine on this site still has me by the short hairs so I have not found any info on one of the key differences between the early and late R4's. I had a built R4 (pre-1986) on a car sold several years ago. The tranny drove me crazy. :banghead: It would shift from first to second whenever it wanted. There was nothing I could do to keep it in first. It did go to a higher RPM shift point under WOT but still was shifting fron 1-2 about 4 grand. No one I talked to could tell me why this was and what I could do about it. Finally asked a techie manning the booth of one of the tranny companies attending a GG show in Pleasanton. He looked over his shoulder at a dude sitting back by their tailer and said to ask him. Turns out it was the prez and guru. :cool: He told me that there was a valve(?) or valve body mod (?) that the later R4's have and, if it had been installed by the tranny builder, I would have been smiling instead of crying. I ended up selling the car about 2 weeks later so never discovered if what he said was true or not.

If this tranny turns out to be a 700R4, I sure as heck want that valve or whatever it is that will allow me to hold the tranny in first as long as I want!

Anybody know the part I'm talking about or what it takes to mod the tranny to hold that 1 to 2 shift?

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