Trans Build Recommendations

M

Michael

Member
Looks like I am in the market for a transmission AGAIN...

Here is the prior thread:
http://www.syty.net/forums/showthread.php?t=51877

After 7k miles on the dealer-rebuilt trans, the same apparent problem has resurfaced (no 2nd gear due to damaged 2-4 band and reverse input drum). GM won't stand behind it (and it was doubly annoying since their call center was obviously in India with people who have probably never seen a GM car much less a Typhoon). I'm guessing that there was an underlying cause that the dealer tech did not find, and only fixed the symptom.

I guess I have a few questions -
1) Does anyone have any suggestions as to what would have caused the repeat failures of the 2-4 band and reverse input drum?

2) Does anyone know of a decent trans builder in the Pacific NW who could build one? I don't mind driving a few hours to drop off the trans. Not planning on anything too serious, but would like to be able to bracket race it with boosted launches when I feel like it. As an absolute worst case scenario I might try to get the thing into the 11's someday, but realistically it will probably stay as a mid-low 13-second ride.

3) Is it worth doing this myself if I have the time? I've never worked on a 700R4/4L60, but have done some of my own work on Powerglides, TH350 and TH400 transmissions. Does anyone offer a decent rebuild kit with all of the necessary upgraded parts to survive?

Thanks,
Michael
 
M

Michael

Member
Re: Trans Build Recommendations

Anyone know what he charges for a build these days? I was going to have him do it last time, but the shipping was going to be expensive, and I needed it back on the road right away (it was my daily driver back then).

It sucks, I used to live in NC, would have been a quick trip down the state to bring it to him!
 
Treymen

Treymen

Donating Member
Re: Trans Build Recommendations

Ditto on wanting to know what he charges, or a reliable knowledgeable builder in western WA?
 
dgoodhue

dgoodhue

BuSTeD 4.3
Re: Trans Build Recommendations

Did the GM trans have the '093' Corvette Servo and the other upgrades for a SyTy or did they stick in a regular Blazer trans. The GM Remanufactured trans should have lasted more than 7K miles on a 13 sec truck.
 
M

Michael

Member
Re: Trans Build Recommendations

According to the part number on the trans itself it was the correct unit, and according to the trans tech at the dealership (he was a friend of GMPartsGuy on this site and apparently knows SyTy transmissions and their unique parts), it had all of the correct parts in it.

I still wonder if there is something fundamentally wrong with the transmission. After a few hundred miles I tried a few slightly boosted (maybe 3-4 psi) launches just to make sure it shifted well under power, and aside from that it's been driven VERY easily for that 7k miles. I would think even a non-SyTy trans would have survived that.
 
M

Michael

Member
Re: Trans Build Recommendations

Just resurrecting this old thread to see if there are any updated suggestions for a trans builder in the NW? My Ty has just been parked all this time but I'd like to get it back on the road this year.
 
Rexxenexx

Rexxenexx

Active member
Re: Trans Build Recommendations

Shipping to Mike Lee @ RPM for you shouldn't be bad. I had one built by BowtieOverdrives and it was a POS nightmare. Leaked at shifter cable, had the WRONG servo, and lost drive if you went WOT. DaveP finally sorted it out, but I still wouldn't take it to Vegas or anything. ;)

I have my original trans out of the car and am also looking for a good trans guy to rebuild it as a "backup." Let us know how things work out.
 
Throws

Throws

Active member
Re: Trans Build Recommendations

I've heard good things about this guy from the people at PSI:

TransAction Transmission, Inc.
3627 Pacific Avenue Forest Grove, OR 97116
(503) 359-9141

-P
 
DaveP

DaveP

Active member
Re: Trans Build Recommendations

Has this transmission been torn down and the failure identified? Or are you assuming it's the same failure mode as the last time, based on symptoms? The band and the drum it rides on are not fussy at all when it comes to durability. The band is also used for 4th, so if it has no 2nd, but still has 4th, it's not the band. The band by itself never fails, unless it breaks the anchor hole boss, or sticks the servo-pin through the pad.

The key to preventing repeat transmission failures is proper diagnosis. Busted parts are fairly easy: If it's busted, replace it. (Although there is usually an underlying cause for the broken part).

"Burn-ups" are different. Burned clutches, bands, drums and steels indicate that the "controls" weren't functioning correctly. Usually something is slipping (because of inadequate pressure actuating the clutch or band) or being applied when it shouldn't be. Could be valve body, line pressure or TV pressure controls. Cracked accumulator pistons, stuck or leaking check-balls, incorrectly installed or damaged seal rings, etc. There are many, many ways to put one of these together incorrectly, or just have a bad day and a seal gets cut during installation, and you won't know it until it comes back burned-up. It happens to the best builders.

The art is in the tear-down to determine the failure point. A burned-up band is the result, not the cause of the "problem". Only a guy that has done many many of these will have the skills to 'find it'. And the same guy will have developed techniques and procedures that work for him to build units that achieve customer satisfaction, and stay "fixed".

Anybody can take one of these apart, replace the bad stuff, and put it back together. But is it fixed? This diagnostic thing gets really difficult when it's been apart, and things changed around (shift kits, drilled separator plates, valve-body mods and changes, "experimental" clutch packs and clearances, etc.).

You're doing the right thing. Asking for recommendations. Try to find someone local, even if you do the R&R yourself. . That way if you have concerns about the way it operates, you can take the entire truck to them for a follow-up visit. You might even volunteer to bring it to them after you reinstall it, so they can double-check the TV adjustment, drive it and check performance, etc. I'm not suggesting you don't know how to do these things properly yourself, but a builder can't be responsible for failures caused by things he can't control. So give him the opportunity to be the final word on "It's OK. Drive it".

Good luck.
 
gnnorthwest

gnnorthwest

PNW SyTy Headquarters
Re: Trans Build Recommendations

Michael said:
Just resurrecting this old thread to see if there are any updated suggestions for a trans builder in the NW? My Ty has just been parked all this time but I'd like to get it back on the road this year.
Click to expand...

Contact Dave Splett up here in Lynnwood, WA. http://www.trans-service.net/

He does all of our SyTy transmission builds. We believe he's one of the most knowledgeable and best trans builders in the PacNW.
 
M

Michael

Member
Re: Trans Build Recommendations

Thanks for the info! The same GM dealer that did the rebuild did the diagnosis, but I don't think they pulled anything apart (just drove it and measured pressures). Interesting about 4th gear not being affected. I was planning to R&R it myself (again...) and bring or ship it somewhere. One other possibility locally is A1 transmissions, they are a well known race transmission builder but not necessarily a SyTy specialist. I left a message for Mike Lee, and will also call the others suggested on here.
 
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