700r4 weak 2nd gear shift

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Obwonkonobe

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So I recently rebuilt my trans, an 89 700r4 with a transgo shift kit, corvette servo, 13 cane pump, boost valve, and a transgo 3-4 spring upgrade kit. Once it was topped off with fluid I took it for a test drive and while I do have all gears, and they do appear to be holding solid, 2nd gear doesn’t have the thud like it used to. Before my rebuild it would go harsh into the gear and chirp the tire with ease even at part throttle, and honestly that’s been my favorite part of this transmission. But after the rebuild it feels lazy and has no real solid engagement. The transgo kit had me remove a spring and snapring from the servo assembly and replace it with shims, and this worked well prior to the rebuild and resulted in a nice positive chirp. And when I rebuilt it I put in new Teflon rings, which have been seated properly, and have reshimmed it, although it took the same amount of shims as before. I’m just not sure what I’m missing. When I pry against the case I can depress the cover maybe 1/8 inches, and the band appeared to have the correct amount of back and fourth play during the rebuild. Sorry for the long post and I appreciate anyone who reads it, but I just want to express how confused I am seeing that I’ve gone through everything I can think of. Does anyone have any ideas of more things I can check? Things I did wrong? And yes my tv cable is adjusted properly!! Thank you, here’s a pic of the “new” trans since everyone here loves pics

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1987 GMC Jimmy

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I’ll play devil’s advocate against you and argue you didn’t do anything wrong. Was this a virgin transmission in terms of mods before you tore into it? Reason I ask is that the B&M shift kit has a reputation for that tire chirping second gear shift. I’ve found the Transgo to be kind of a light crisp feel in terms of shift feel. It’s not mushy, but I wouldn’t mind a notch or two firmer either. Also, did you use Dexron? It’s said that Type F can help bump up the firmness in shifts, but I’ve never tried it.
 

Obwonkonobe

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I’ll play devil’s advocate against you and argue you didn’t do anything wrong. Was this a virgin transmission in terms of mods before you tore into it? Reason I ask is that the B&M shift kit has a reputation for that tire chirping second gear shift. I’ve found the Transgo to be kind of a light crisp feel in terms of shift feel. It’s not mushy, but I wouldn’t mind a notch or two firmer either. Also, did you use Dexron? It’s said that Type F can help bump up the firmness in shifts, but I’ve never tried it.
It was rebuilt to a stock referbished condition the first time before the shift kit andmy rebuild. I’d heard that b and m wasn’t too good on quality so I went transgo, and was fairly pleased before my own rebuild
 

1987 GMC Jimmy

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I don’t think it is. That’s why I also went Transgo. I think the accumulator springs are one of the weakest points on the B&M, and that’s why people complain about the shift feel. And the fluid? Dexron or Type F?
 

Obwonkonobe

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I don’t think it is. That’s why I also went Transgo. I think the accumulator springs are one of the weakest points on the B&M, and that’s why people complain about the shift feel. And the fluid? Dexron or Type F?
Dexron, just genaric Autozone stp brand, I may pull the pan and check the side to side band clearance, but before that I’ll remove one small shim because I have a bad feeling I went overkill and set it too tight. Is there something I can check in the valve body if I drop it?
 

Matt69olds

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If it’s a new band, and you haven’t driven it much, it may take a little driving before the band and drum take a set. As long as it’s a solid shift, it’s probably something that can be fixed with the valve body.

Did you replace the separator plate? If so, maybe the feed hole for 2nd gear is smaller in the new plate. Did the TransGo shift kit offer any tips on firming up 2nd gear? I know the 4L60E kit has additional washers you install under the accumulator piston. That limits the piston travel, making the shift quicker.

If the shift is solid, just not firm, I’d drill the 2nd gear feed hole a little bigger. If that’s not enough, limit the accumulator travel. If all else fails, you could tap and plug the 2ng gear feed hole with 1/8 setscrew. That will completely eliminate any accumulator function. I have done this many times on 2004R transmissions for high powered Grand Nationals and Turbo Trans Am. Unless you have a pretty loose converter, that’s guaranteed to knock the dash out of the truck! Good luck!
 

Obwonkonobe

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If it’s a new band, and you haven’t driven it much, it may take a little driving before the band and drum take a set. As long as it’s a solid shift, it’s probably something that can be fixed with the valve body.

Did you replace the separator plate? If so, maybe the feed hole for 2nd gear is smaller in the new plate. Did the TransGo shift kit offer any tips on firming up 2nd gear? I know the 4L60E kit has additional washers you install under the accumulator piston. That limits the piston travel, making the shift quicker.

If the shift is solid, just not firm, I’d drill the 2nd gear feed hole a little bigger. If that’s not enough, limit the accumulator travel. If all else fails, you could tap and plug the 2ng gear feed hole with 1/8 setscrew. That will completely eliminate any accumulator function. I have done this many times on 2004R transmissions for high powered Grand Nationals and Turbo Trans Am. Unless you have a pretty loose converter, that’s guaranteed to knock the dash out of the truck! Good luck!
The kit had me plug a hole near the 2nd gear servo, and I’m going to play with the shins this weekend. The kit only says to use the washers to adjust. What’s this hole I can drill out? Even though it’s a daily I don’t mind harsh shifts, just makes all my drives more enjoyable
 

Matt69olds

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