700R4 Hard Shifts After TV Cable Adjustment - Third Generation F-Body Message Boards

mpa53167 · 08-27-2009, 08:28 PM

I recently installed a new engine in my 1992 Z28. I used the existing 700R4 that was working fine when I removed the engine (sat for 1-1/2 years in garage with no tranny fluid). After installation, I set the TV cable to the book method and experienced late hard shifts from 1-2 and 2-3. After researching this forum, I tried the transfixleo method with the same results. I even tried disconnecting the TV cable, assuming I'd get quick shifts...same issue.

I'm pretty sure the cable is connected in the transmission. Is the governor bad? Did this happed because I left the tranny sitting for a long period with no fluid? Any help would be appreciated.

Thanks,

Mark

t-top havoc · 08-27-2009, 10:49 PM

See the thread "when do you need to adjust the TV cable" by Gumby.Maybe you'll get something from it as far as adjusting.

Did you take off the trans pan? IDK--if the inside of the pan was rusty maybe some of the bbs rusted//stuck in a couple fluid passages in the valve body? Replaced the filter?

mpa53167 · 08-28-2009, 05:23 AM

Yes. I took the pan off when I removed the engine and transmission. I didn't see any rust. I replaced the filter, front and rear seals, the TV cable seal, and the filler tube seal.

Am I right in assuming that disconnecting the TV cable completely should lower the shift pressure and cause quick shifts?

Thanks.

transam85dudeman · 08-28-2009, 06:21 AM

Hey dude, where did you pick up your TV cable seal, speedo seal, and dipstic seal. I need the seals leaking tranny. and to fix you Tv, call the cable company, JOKE>ha< but seriously i had the SAME problem. ill post the copy text of my solution below.

(from http://www.thirdgen.org/techboard/tr...early-new.html (Still shifting early with new prop. adj. TV cable) )
ya, dude dont drive it around with late shifting man. when i had my car diagnosed like two years ago at a shop that didnt know squat. they purposlely messed up the and adjusted my transmission throttle valve cable (t v cable) for premature tranny failure. i ask them y it was shifting messed up, they said the tranny needed to be rebuilt or better yet a new one. just didnt make sense. i fixed my probelm by 1. pushd and held the 'gray button' on the cable in, 2. pushed back the black slider then released gray button 3. pushed and held the gray button and manually opening the throttle body manually using the tb lever to wot 4. released the gray button 5. test drived it, and perform my little procedure, (made it up) i would drive down a abandoned road about 300 feet gradually speeding but not past 25 or 30, then stopped, popped the hood and pressed the gray button in and adjusted the slider two clicks forward, or backward, then released the gray button. It took 5 minutes but i found the sweet spot. its been two years or so, daily driver and the tranny is fine, just a leak, but soon fixed. and also youll burn up your tranny driving around with a bad tv cable adjustment, im talking about a brand new tranny, burned after 300 miles. and not to mention the dang looks people gave me..

mpa53167 · 08-29-2009, 07:38 AM

I got the TV seal from NAPA, but had to order the dipstick tube seal from Rockauto (part# 1259475). I didn't replace the speedo seal.

I've tried adjusting the cable slider all the way forward, all the way to the back and many spots in between with the same result. Hard/late shifts.

What should happen to the shifts if the cable is completely disconnected.

Thanks.

transam85dudeman · 08-29-2009, 10:02 AM

Quote:

Originally Posted by mpa53167

I got the TV seal from NAPA, but had to order the dipstick tube seal from Rockauto (part# 1259475). I didn't replace the speedo seal.

I've tried adjusting the cable slider all the way forward, all the way to the back and many spots in between with the same result. Hard/late shifts.

What should happen to the shifts if the cable is completely disconnected.

Thanks.

if the cable is disconnected, i heard of tranny failures.

fernando rs · 08-29-2009, 07:37 PM

Hey does yor tranny have a vacuum modulator? It could be the modulator,or the vacuum line that runs from the modulator to its vaccum source at the intake.Check if the line isnt cut or disconected.

mpa53167 · 08-30-2009, 06:19 AM

No, the transmission does not have a vacuum modulator. I believe the TV cable does the same thing as the vacuum modulator on older transmissions.

Dropped the pan yesterday. Everything looks fine. The valve connected to the TV cable moves freely when the cable is moved. What other things can I look at and check with the valve body?

Grinch Racing · 08-31-2009, 03:50 PM

Id look for a stuck governer.. No 700r has a vac. modulater on them.. the t.v. cable will change shift points but, in a 700r to get a shift your governer pressure has to OVERCOME throttle pressure... if your governer isn't stuck and the valve moves freely then you would need to look at throttle valve sticking.. i know it was said the plunger on the throttle valve moved freely but there are more valves toward the front of the v.b. that run off that plunger and are prone to stickin.. my money is on the gov...