FruityOne

Hey, I installed a shift kit in my 700r4 and now it shifts either early or late, even though the shifts are still firm.

The basic run down.

the 1-2 shift is early ALL the time. Weather just cruising, or WOT. At WOT the 1-2 upshift occurs at 3,900 or 4,000rpm. It should be around 4,500rpm as thats what it did before.

The 2-3 upshift is late, and requires almost letting off the throttle at part throttle to make it shift. I will shift, it just shifts higher than it should. At WOT the 2-3 upshift occurs at 4,900rpm consistnantly. The shifts are firm though.

Also, on a WOT downshift the RPM's will shoot up a bit, but will engage solidly. I've got a video to explain it a bit better.

I have already adjusted the detent cable succesfully, and it doens't feel like its slipping at all. I've been through two transmissions previously that were slipping. And this one is not.
http://student.dpg.devry.edu/~d00712.../gta_0-100.mov

FruityOne

No one has any ideas?

IROC_385Z

Sounds like what mine did ever since I had a shift-kit put in...I never did figure it out. Now i'm waiting for it to get back from the shop from the second shift-kit install! Tranny's are NOOOO FUUUN!!!

kd5boc

almost sounds like a TV system being clogged...your 23, and 34 shifts were a little low too...well...I just got used to mine

See if a local tranny shop can flush your system, then try again...one of your passages might be a little clogged.

Nice vid though...sounds good

Tom

Morley

You are going off the stock tach? Don't trust that thing as far as you can throw your car.

If you feel it is accurate enough.... Set the TV cable per the manual, then lengthen it 1 click and try your run again. If it still is wrong, lengthen it 1 more click (don't go more than 2 total clicks) and try again. Still no go?? Have the trans completely flushed, filter changed and good quality fluid put back in and try again.

FruityOne

The stock tach is accurate enough to determine changes in how its shifting. Even if the numbers aren't accurate.

And what are you on? The 2-3 shift is low? Watch the video, the 2-3 shift is WAY too high. 4,900rpm? Its wrong, doens't pull at all up there.

The shifts should be about 4,500rpm all around.

There is no 3-4 upshift at full throttle. I let off the gas and let it shift into 4th.

Riley's35089rs+

try Leo's way

Start with correct TV setting: To adjust the TV Cable skip the book method and do this: Press the 'D' shaped lock button on the adjuster and loosen the cable setting (The black housing that the metal cable is in will move forward). Now, have someone floor the gas pedal while you check to see if the throttle plate is open all the way. Usually they are off a little and will wiggle. Do whatever you have to do to get it open solid. Now, with the pedal still floored, press the 'D' button and pull the cable casing (the black tube) back as hard as you can (putting maximum tension on the metal cable) and release the button. You now have the engine, tranny and gas pedal all in sync at WOT. Mark the cable casing so if for some reason it gets moved you can know where to put it again. The problem with the 'self adjust method' is that it bends things and puts them permanently out of whack. It is also the full TV setting, which is theoretically what the GM method does.

Gm's way.

GM 700R4 Throttle Valve Cable Adjustment
1. Remove air cleaner on vehicles with carb or TBI.

2. Depress lock tab down on TV cable and push cable all the way forward towards carb or injector.

3. Have someone sit in vehicle and depress gas pedal to the floor so it's at WOT (Wide Open Throttle). Hold it there for steps 4 and 5.

4. Now check to make sure the carb arm is bottomed out or has no more movement. If not, use a pair of Channel Locks to bend TV cable bracket until carb or injector arm no longer rotates.

5. Next, depress lock tap down and pull TV cable back (Pull HARD!) towards firewall or away from carb or injector until it stops and then release the tab.

6. Use a pocket knife or hacksaw blade to mark the cable in front of the snout. This is MAX TV.

7. After marking Max. TV depress lock tab and push cable forward toward carb or injector 1/8'' of an inch. Make a mark in front of snout. This is Minimum TV.

8. Set cable back to Max. TV and Road Test.

FruityOne

That still doesn't explain why the 1-2 shift is low, and the 2-3 shift is high.

I've experienced an incorrectly set TV cable, and a worn out TV cable before. The shifts are consistantly off, all in the same manner. Not one shift is high, and the other low.

Try again, this is a valve body issue that isn't related to TV cable setting. Whatever the problem it exists its in the valve body, not the cable settings. Adjusting the TV cable will not fix this issue.

Morley

Well, since you already know its valvebody related and you just installed a shift kit...guess what time it is.

Riley's35089rs+

Didnt mean to insult your inteligence, Even the best overlook things at times.......

FruityOne

I know i need to tear the valve body out.

I guess the question I have is too specific for anyone but a trans guru to answer.

I'm looking for information on exactly which valves I need to look at. I'll need to get new gaskets for the seperator plate, and I'll probably tear the servo assembly out to inspect the sealing rings on the pistons. The trans was rebuilt less than 500 miles ago. And then I put the shift kit in.

The reason I asked hear instead of asking the TransGo tech support is because they were *******s to me. They wouldn't help me to trouble shoot anything.

As for the tach being inaccurate. Yeah, it may be. But its consistantly inaccurate. So its still usefull for determining if its shifting high.

Morley

Bear in mind that you could actually have 2 problems at work here, the valve body on the 1-2-3 shifts and the 4th gear pressure switch on the 3-4 shift. May have damaged the wiring to the switch or it may have just decided to fail at the worst time.

Riley's35089rs+

PM," Pro Built Automatics", He might be able to help you.

https://www.thirdgen.org/techbb2/mem...hreadid=240591

FruityOne

The 3-4 shift is fine. I have never been in a F-body automatic that will shift to 4th gear at WOT.

If I hadn't let off the gas the car would have stayed in 3rd till I blew the motor up. Just the way it is. I think only B4C's got a valve that allowed them to hit 4th gear at WOT. I'm aware that B&M makes a valve that will prevent the 4-3 downshift at WOT above certain speeds.

I most definitely believe that the early/late shift issue for the 1-2, and 2-3 shift is in the valve body. Thing is, I don't know the first thing about the valve bodies layout. I know where the TV plunger assembly is simply because the TV cable connects to it (Duh!). But the 1-2, 2-3, and 3-4 valves aren't quite as easy for me to find.

SSC

It sure does sound valve body related.

What type of kit was this? I installed a fairbanks kit a few years ago and from that point on was never happy with the way it shifted, also a fairly early 1-2 late 2-3, 3-4 was alright.
If you replaced the springs in the shift valve-s its quite possible they were not re installed correctly or were damaged.


Auto transmissions just suck!

greezemonkey

iTrader: (14)

Fruity

Did the kit require you to change or remove the 1-2 and 2-3 accumulator springs? I can`t seem to view the vid but a late third can be a problem with the accumulator piston cocking in the bore if the spring isn`t there any longer.I just ran across this problem in a th700 that we put in a jeep cj...roll down the street in second until you let off a bit then it clunked in third. Turned out to be in the 2-3 acumulator piston/bore. The early second probably isn`t anything to worry about, I mean if your kit had you change out the pressure regulator spring for the pump it might just do that early thing. I`ve had all the kits and I have always had a early second. You can correct that with the govner wieghts and springs but that`ll delay all the shift points under WOT.

FruityOne

It was a TransGo Shift kit with the video, vette servo, and .500" boost valve. And yes, I watched the video too.

I have a type 2 valve body if that helps anyone. The instructions had me change some of the springs out, however it doesn't label what valve I'm working on.

The instructions just show a valve and says change this spring to this color. I called up and complained about that and the responce I got was "Well, too much knowledge can be dangerous." I got pretty pissed at that point and asked for his supervisor since the guy was being such a dick.

The idiot didn't know anything about the trouble shooting aspect. Just kept going "redo the shift kit....." Well I'd already been over the steps twice with him and had the valve body down 3 times. I got so pissed I don't even want to call them back.

Morley

Try here Fruity http://purplesagetradingpost.com/sum...o/700R4p4.html

Some info on how to test your problem and how to fix it.

FruityOne

Thank you. This info gives me something to look at because I DID install a .500" boost valve, as well as different springs (as the TransGo shift-kit instructions have said).

Wonder if I may have grabbed the wrong spring by accident, or something else.

Captain C

I've had three 700R4's with a Transgo shift kit in them, including my current one which was built by Probuilt. All of them needed the governor modified to shift at the correct points afterward.

What you are describing is what I went through and was probably the cause of the early destruction of two of the transmissions. I am currently running a narrow tab governor with an orange spring and a light green spring. The car upshifts at 5500 1-2 and 5500 3-4. I haven't had time to take it out to try the 3-4 with this spring combination. I did a full throttle upshift at 5000 with an earlier combination of springs. Only problem with this setup is that 4th gear won't lockup until 53 mph. If I drop to the dark green spring instead of the the shift points drop about 500 rpm but around town drivability is like a stocker.

IIRC, the light weight full tab governor with the Orange/Light Green springs shifted at 4700 1-2 and 4500 3-4. I don't have my chart in front of me to verify that.....

Probuilt is definitely the guy to get your transmission from. This car shifts smoother than a stocker and he backs up his work!!!!!!!

I love my Edge 9.5" 2800 rpm lockup stall convertor. It's way easier on my differential and works well on the street so far.

IROC_385Z

After I had my transgo put in the trans wouldn't shift AT ALL till like 4000 and refused to shift full throttle until over 6.k...My cam only revved to 5800 MAX! Needless to say I have it at the shop again and I hope that it gets done right this time!

LB9GTA

iTrader: (1)

I changed to a trans-go shift kit. Had the same problem. What I had to do was the tv cable then do pressure test on the tranny. Obviosly you need a pressure guage. My pressures did not go up when I idled up to 1400rpm(when the convertor stalls). Fixed the pressures and it shifts awesome!! Right at 5000rpm where I want it or sometimes higher works better for me.
LB9GTA

Captain C

You definitely have to make sure your pressures are correcrt first!!!!! You'll fry the trans if you don't....

FruityOne

No access to anything to check the line pressure of the transmission.

Like I said, the shifts are solid. Video shows this. No hesitation or anything. Just that the shift points are off.

So by changing the weights/springs in the governor I can control the shift points for the different shifts? Can I alter just the 1-2 shift, or just the 2-3 shift? Where to I get the parts to do this right. Anyone care to point out a nice little site that explains how the changes affect the shift? I assume that using a softer spring would cause the transmission to shift earlier. And that a stiffer spring would hold it in the gear a little longer.

I probably won't attempt anything for a while. But more information would be nice.

Any place to get a gauge to check the line pressure? A place to rent it? Cause I'd rather not take it to a shop and have them check it out. They'd probably charge me $60 and ask me to bend over while not telling me anything I didn't already know.

SSC

Yea but dinking with the governer weights/springs will change 1/2-2/3-3/4 shift points in fairly equal amounts. It wont make 1-2 shift latter and 2-3 sooner ect. Thats controlled by the springs in the actual valve body.

I persoanlly dont care for shift kits in general these days most people just want the shifts a tad firmer and you can do that easy, you pay more for the transmission fluid then the actuall parts.

FruityOne

Okay, so my earlier assumption about the governor was right. It affects all shifts equally, just like the TV cable in a sense. Doesn't single out any specific shift.

I knew it was in the valve body. Looks like its time to talk to transgo and get some info on the springs they use. Cause I may need to change them.

SSC

Yes and no, it effects shift in a fairly equal manor. It might increase or decrease a certain shift point. An example would be you just grabed a governer with a different weight assembly and slaped it in. Now 1-2 is higher 400 rpm or so but 2-3 is only 200 rpm higher then it was. But yes most of the sequential points are goverend by the springs in the valve body like mentioned above.
What these kits do have you replace the springs with different ones usually firmer. This increases the amount of pressure required to pop the valve full open for the shift allowing the gear to hold longer. I personally prefer stock shift points with a tad of accumulator firming to increase the shift feel.

I would talk to transgo again and see what they have to say before getting soaked in ATF again. I sure hope you installed the $7 drain plug.

Captain C

As an example. I used the very light weight Light green spring on one side and the dark green spring (next step stiffer) on the other side. The upper RPM shift points wer fine, but my normal around town shift points went to pot. The 1-2 shift points were livable at 2250 being the lowest they would upshift, but the 2-3 shift point went to 2750 for the lowest it would upshift. That's 45mph in 2 before it would upshift to 3.... Not good!!!!!

If you know of a local trans shop that installs shift kits, see if they have some governor springs you can have,or at least buy cheaply. there is at least one place on the internet that sells a governor modification kit. But you need to start with the correct body first. Consider going to a wrecking yard like "Pick-a-Part" or something of that nature. A place where they let you take off the parts yourself thus getting the parts cheaper.....

The governor bodies you will want to start with are as follows: One with a thin weight on each side. This will have a full square tab. This was the one used on 305's in Camaro's and FB's IIRC.

Look carefully as some have more than one weight on each side, others will have a thicker weight on each side.

The one I am using has a thin weight that is shaped like a pyramid on each side. It has a "narrow tab" at the top, thus it's designation. I believe this was originally used on Y and F bodies with the 350. (I could be way off on the engine/model information as the sheet I was looking at was very blurry due to a lousy scan job by the person I got it from. But the description is correct.)


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