Help please guys.

I've got a 1989 TA GTA with TH700R4 transmission, with several engine mods and a dyno proven 386lb ft at the rear wheels but the car has a bit of a problem.....

When driving on the highway I can gun it hard off the line on the sliproad and keep it WOT. It shifts into 2nd at ~55mph at ~4500-rpm then it doesn't shift again. I can keep it gunned at wide open throttle till 125mph and it still doesn't shift. Last week I kept it at WOT till 130mph at ~5750-rpm before braking back down to more legal speeds. The same problem happenned when the car was on the dyno last month.

Can anyone help? What is wrong with this trans?

Thanks for your time guys,

James

 

The car has only 40000 miles and is not a daily driver. However, it is driven hard. I have a receipt from the previous owner for a transmission overhaul from 5 years ago.

Any ideas guys?

 

check the TV cable

 

yeah it melted on the exhust and we though when it got replaced it would b fine but its still not

 

but it IS ADJUSTED correctly??? if its not that then. you need a tranny rebuild. your clutch packs are probly burnt up..along with your band.

 

ok ill have a look into it, cheers

 

I got someone to check the cable and they say it's properly adjusted.

However, I have a B+M Megashifter which the previous owner fitted and am worried about it. I recently lubed the ratchet and replaced the bulb (with an LED). It has a very stiff action and can't be put into 1 or 2. Will only move through P-R-N-D-3. Should I consider replacing this before looking at the trans?

 

adjust the shifter cable at the transmission (drivers side or the tranny pan)

 

Thanks Fattie.

I'll try that.

However, I'm seriously thinking a rebuild is called for - but wait that new safe for 700bhp trans from Art Carr is calling me........ On special at the moment as well.

 

rebuilds are goodd... but expensive! i just had mine done ans spent 1700 .. but comes with lifetime warrenty

 

you say's it shifts 2 @ 4750. what u feel is 2-3 shift.

the 1-2 shift at wot occurs around 30-40MPH.
the 2-3 shift at wot occurs around 65-80MPH
the 3-4 shift WOULD occur around 120-130MPH


5750 @ 130? at those speeds you are in third.
no way in hell that u are in second gear.
(i should know )


in essence you have no WOT 3-4 correct?
that is what almost every 700R4 around here experinces. you have to change a couple of valves/sleeves in the valve body to get that 3-4 WOT upshift. the B-Car Fix kit is what u need. #8673948 it's much better than the B&M crap.

 

I heard that!!!

Unless you have a 2.00 rear gear (literally, I did the math), your in 3rd.

I bet you have 3.23???

BTW: If you had a 2.00 rear gear & the HP to achieve this, you could go 318mph @ 6000rpms in 4th with 26 inch tires.

Ron

 

no we have seen this on a dyno graph, the car shifts down when u WOT into 1st as it cruises in upper gears, then shifts to second and doesnt come out of it. i know about WOT valves and its not the problem im sure.

we dont have stock gears i dont think as the 0 - 60 aint to gr8 but the 60-100 is smashing, ill have a looki into the ratios and see if i can clarify what ratios we have, but i have considered going back to stock ratios as i want a better 0 -60

 

Listen, if you are cruising around in third or fourth at normal operating RPMs and hammer the throttle, I garuntee you that you are not downshifting into first. You are dropping into second and than it upshifts into third. The mechanical relationships of the gears in the rear axle and the transmission and the engine RPMS just don't jive with what you claim the speeds and RPMs are. But I guess you are going to have to check on your gear ratio to convince yourself. If your 0-60 isn't all that impressive you likely have the 2.77:1 gear since the only gears available in the 9-bolt differential that came in GTAs for that year were 2.77 and 3.27. If you had the 3.27 you would not be all that dissappointed in the 0-60.... I am willing to bet, along the lines off the rest that have commented here, that you need 3-4 WOT.

As for the shifter, if it won't go down into first or second get rid of it or find out why it won't and fix it. Not being able to select the gear in an automatic is a PITA in the first place, and doubley so without a functioning shifter.

 

well there is only one noticable change when we go from a hard standing start aswell, I'll have a look at the ratios.

I've had a few friends in the car and they only feel one shift too - also only one change in the revs etc.

 

mystikkal

I have that upshift kit sitting in my bedroom but I have no idea how to fit the damn thing. Anyone know?

As for the car. I've been it the car when it has gone from a stop to 120mph and it only shifts once and that is at about 55mph at about 4500rpm. My only guess is that it would be missing out second completley. Is this possible?

RMK

 

Double check their "check". B&M should be able to mail you the instruction sheet for the cable. You can't just look at it and determine it's adjusted correctly.

As for it being hard to shift, I just had this problem. When I got the shifter, it was a little harder to move than the stock shifter-- no problem. Well it was IMPOSSIBLE to move, and the car wouldn't stay in park anymore. I went under the car and redid the cable adjustment, it was dead on, but the cable couldn't move the tranny's shift lever into the park position. So I replaced the cable- what a world of difference! Shifting is so easy now, and the car always goes into park. 'Fact, when I took the old cable off, I twisted it into a circle (like it was installed on the car), and tried to work the cable by hand. It did NOT budge. Tried the same twist with the new one- the cable slid easily inside the sheath. Here's my message about it: https://www.thirdgen.org/techbb2/sho...hreadid=126924

 

RMK,

i also have the kit but have not installed it yet. i haven't had the time to do it. also my other two babies are out of commission. the red roc RIP(it has cancer). my green one, head swap. i will hopefully have some free time to do it in november. hearing Klayburn's misfortunes with the kit is kind of discouraging. i will attempt to install it regardless. i will let you guys know how it goes.

 

The 2-4 band is gone that is why you can do 130 mph. You are making a 1-3 shift, that accounts for no 4th gear. If you are getting 2nd gear, then the problem is with getting overdrive. What shifts do you have?, a 1-2-3 or 1st to 3rd shifts?

 

mystikkal,

I had not heard of Klayburn's misfortunes. I'll do a search and read up. I probably wont get mine fitted as the trans has seen better days and I have my heart set on a ProBuilt early next year.


ProBuilt,

It's been a while since I've been in the car but I think that it's doing a 1-3 shift.


RMK

 

TomP - thanks ill have a look into that, the cable had been sitting on the exhaust manafolds and melted, so it was going ot be replaced but there was spare cable so it was just joined together. Will go under the car now and see though