GMTech

Thats the beauty of the TransGo kits. They have a "special" self cleaning Throttle Valve, as well as dual booster springs. They are almost impossible to get stuck. I have seen tons of stock 700's stick, and NEVER saw a TransGo valve stick. They spend a lot of time engineering parts to fix common problems like this one.

And like I said earlier, if you read the instructions carefully, you were supposed to remove washers untill the band would "wiggle", THEN remove an extra thin washer. This has always resulted in proper clearance on the ones I have done, although I quite using the washers because it can make a "bang" shift.

ArrioZ28

Its a pipe threaded (tapered) plug located forward/above the servo on the drivers side. It is the only plug in that area. It will be rather tight since it is a pipe thread.

LT1guy

iTrader: (1)

Are you talking about the valve that is installed in the case, close to the filter, with the snap ring? I had a lot of trouble with that part. Any suggestions?

ZaphodB

Yes, thats the pressure regulator valve, Reverse Boost Valve and TV Boost valve, and then snap ring at the bottom.

ZaphodB

But when it comes to the 2-4 band adjustment I've followed the instructions very carefully, the band can be wiggled as much at it should.

I have used 2 large washers and 2 thin ones.

Because with 3 large it won't even close, and the instructions say remove large washers until it fits, then check band clearance and if neccessary remove one more thin washer....

If the pressure valve is okay, and the 2-4 band is okay, what the next thing to suspect?

I am going to go out to the garage and look thru the valvebody, remove all parts I replaced and take some pictures of the order and where I put them and see if someone can make anything out of that?

LT1guy

iTrader: (1)

I had a heck of a time getting all the parts up in there (piston, spring, etc), and once I finally did, there was very little travel...the assembly would push up a little (once the snap ring was installed), but it didn't seem like as much as it did in the video.

ZaphodB

Do you have the same problem as I do or did your work after the install?

LT1guy

iTrader: (1)

It hasn't been driven yet, but the reverse and neutral detents both are now drive gears...the car goes forward in every gear but park.

white89_350

I put the old TV boost back in.

I took out another washer too.

While I have the pan off is there anything else to check on before put it all back together. I do not have the VB off.

Once again I can not get 2,3,4th gears for those wondering why I did what I did(TV Boost and washer)

I have to go to work I'll be back online after 10pm.

ZaphodB

I have checked all new valves in the VB, all were ok and moving freely.

Checked the 2-4 band servo & band, also ok there.

Checked pressure regulator, Reverse boost valve, TV boost valve also okay.

All checkballs where they're supposed to go also.

But, I discovered when looking into the upper valvebody into where the 3-4 accum goes that both passages are now plugged after installing a plug where Transgos instructions told me to.....

Is the other hole plugged from factory or might the previos owner of the car have put that other plug there?

If both holes are plugged, how does oil get into the 3-4 accumulator?

ZaphodB

I also tried the old TV boost valve, and that did not solve my problem either.

I have double checked everything I have touched inside the VB and it's all according to the what the manual says, no stuck valved anywhere, and in the 2-4 band servo I have 2 large and 2 small washers.

And I took it apart to make sure that no seals were damaged and they looked fine...

What else is there left to check? I have one suspicion, on my tranny one of the holes in the 3-4 accumulator was already plugged, and when I plugged to other one, as told by the manual I am starting to wonder how the oil should ever get into the 3-4 accumulator?

And if there is no oil there, why should the yellow spring and the piston even be up there, they serve no use if the piston is not supposed to move because all oil passages are blocked off?

white89_350

The 3-4 accum. if pluged there why no 2nd gear?

white89_350

With two of us having the same problem with the same kit why is there not a simple answer?!

ZaphodB

Okay, lets go thru each step we have done of the install and see if someone might see an error in there: (First note, I have second type VB).

1. We have replaced the Tv Boost valve and Reverse boost valve, thats checked and okay.

2. We have replaced the TV valvetrain, it moves freely and is okay.

3. We have replaced the Line bias valve & spring and added an endplug because the new valve has the spring on the other side of it compared to the original one, it moves freely too.

4. We have replaced the 3-2 control valve & spring & endplug, checked that that too moves freely.

5. I have drilled three holes in the VB, where they say they should be. See the following pictures for details:

http://www.area51.cc/~zaphodb/IROCZ/...ansgoShiftkit/

6. I use two checkballs in the VB, and four on the plate, and they are in the locations specified.

7. I have plugged holes 5, D and F on the separator plate, enlarged hole G to 0.110", enlarged holes A, C and E to 0.157"

8. Put tapered plug in 3-4 accumulator housing (Now both holes are plugged there, because the other hole was already plugged when I took down the accumulator piston. Should it really be this way?)

9. Put tapered busings with .063 holes in the two locations thay specified should have them.

10. Replaced the 2-4 servo parts in the proper order, used 2 large washers and two small ones, band clearnace is withen limits (1/16" - 3/16").

11. The 1-2 accumulator contains the following parts from the bottum and up: two washers, blue spring, piston, black spring , then checkplate, 3-4 accumulator conatins yellow spring, then piston.

12. The aux valve body still contains one checkball in its proper place.

13. The garage contains a very confused novice mechanic who scratch his head and is wondering what went wrong

ArrioZ28

I think I'm pretty sure on this but I think that the servo pistons on both the 2-3 and 3-4 accumulator go to the bottom of the bore. I am not sure what the effect is if reversed to the top of the bore. I'll try to do some reasearch in this.

ZaphodB

You're right, the original design is piston at the bottom, then yellow spring.

The Transgo kit wants it to be: 2 washers, blue spring, piston, black spring, then separator plate, then spring for the 3-4 accumulator (Original yellow, or should it be the black one that I also put in the 1-2 accumulator?), then 3-4 accumulator psiton.

But here's something that I am thinking about: In the video they stick the black spring on top of the 1-2 accumulator piston, then just before they install it, they say to put back the spring for the 3-4 accumulator on top of the plate.

Nowhere do they mention if they are refering to the original yellow spring for the 3-4 accumulator or if they mean that the black spring should go ontop of the checkplate, into the 3-4 accumulator.

Right now I have two springs in the 1-2 accumulator, the more I think about it the stranger it sounds to me.

Should there really be springs both under and over the 1-2 accumulator piston?

ZaphodB

No, thats not the problem either. I've learned that the accumulators only purpose is to make the shift softer, so blocking off the 3-4 accumulator should only make it shift harder.

So this is not the cause of our problem either

I tried both calling and faxing Transgo about a week ago, but there's never any answer on the phone, and they haven't responded to my fax either.

Have you had any success in contacting them about this?

JP84Z430HP

Just to get this straight, which it pretty much seems to be, from what I've learned over the past couple years, the checkballs, and accumulators and accumulator springs will not keep it from shifting. I am not an expert on these things, but I would think that as long as the accumulators have good seals on them, (or would it even matter?) they will not keep it from shifting....

This thread is becoming a learning experience for me to learn more about how the 700 works. Unfortunately, I don't get to work on all that many of them, most of the tranny's I work on are 4L60E's, which are mechanically pretty much the same, but the valve body is very different, and not only because of being aluminum!!

Are there any good books out there that explain exactly how the valves in the valve body work and interact with each other? The service manual has the fluid flow charts, but I don't have alot of exerience in reading these. Maybe I should just sit down and look them over better.

GMTech

A "missing" checkball will only cause a harsh shift. It will allow un-orificed fluid to the apply device causing an uncontrolled (hard) apply.

A "mislocated" checkball can cause shifting problems as it may block a feed orifice or otherwise hinder fluid flow from going to where it needs to go to make a shift happen.

A blocked off accumulator will only cause a harsh shift. TransGo has you block off the 4th accumulator to render it useless, then has you invert the piston since its not functional.

A leaking accumulator on the other hand can cause other issues. If you allow apply fluid to bleed off, you can have a very soft shift or slipping. We just had a run of 4L80-Es with undersized accumulator seals causing 4th gear to slip. It was hard to beleive that simply replacing a tiny square cut accumulator piston seal would restore 4th gear, but the proof is in the pudding, so to speak.

I know the 1-2 accumulator setup sounds wierd with a spring on both sides, but if you understand how the accumulator circuit works on the 1-2 shift, its actually BRILLIANT and I only wish I would have come up with it first.

When you say you drilled three holes in the valvebody, I'm hoping you mean one through the partition in the "bathtub" and two in the 3-2 control circuit, right?

ZaphodB

But could some of the parts in the valvebody that I didn't touch have gotten stuck?

Because as many have said already, if the 2-4 band would have been shot/wrong it'd still skip to 3:rd... Which it doesn't!

ZaphodB

Yeah, one in the partition in the bathtub and two on the 3-2 control circuit. (One down into the bore, and one two passages to the left that went thru the outside of the valvebody).

In short, I paid attention to the instructions, I only have holes where they want them.

And what spooks me most is that I don't even get the car to skip into 3:rd, because it should skip 2:nd if I accelerate enough in 1:st, so it has to be something major wrong with this...

What is so vital to shifting that no gear but 1:st and reverse works? The 2-4 band shouldn't affect 3:rd gear for example...?

white89_350

Yes to the GM TECH. Thankyou for your help. So far you are helping me check off what is right. The check ball mis-placement may be where I refocus my attention if my current fix has no result.

white89_350

Took the test run and still no 2,3,4th gears. I just tookout one thick wassher for more play in the 2-4 clutch band, and reinstalled the old TV boost valve.

Should I take off the valve body and check inside? Should I use the big checkball somewhere, since I did not use it at all?

white89_350

I think TRANSGO should have someone involved inthis. Atleast have a web site with a problems section!

ArrioZ28

Don't bother reinstalling the large diameter checkball. It will not improve the situation. Leaving it out is the better thing to do at this time. See my explaintion about the copper colored safety checkball above.

Something else to concider:
Ensure that the 4th servo piston, on the 2-4 servo, is not installed upside down (easy to do). Its the outermost piston that fits into the servo cover. Verify that the short (worn /shiny) side of the center land is against the servo pin, and not up into the cover. There is about a 1/4 inch differnce in hight of the center lands.
And, The center aluminum ring in the 2-4 servo assy. should be installed witht the 6 external notches facing outwards.

Also if you replaced the valve body gaskets, verify that that you used the correct ones. There are different gaskets for the early 82-86) non auxilary VB than for the 87-92 aux. VB version. Hold each gasket seperately to the VB plate and check that no holes are blocked, or that any passage lands on the VB or case are not sealed (crossleak).

ArrioZ28

One would think that the 2-4 servo has nothing to do with 3rd, but it does. It also serves as the 3rd accumulator.
It looks as though if the center aluminum ring is installed upside down, the o-ring may not seat on the lower servo wall (reduced diameter), and then blow off 1-2 presure.
Well, its something to check......

JP84Z430HP

Hmm, new light on the matter?

I found what I was looking for in the way of documentation, but I only have it at work, unless I want to pay $15. Alldata has a pretty good description of what's going on, at least they do for the 97 K-1500 that I'm signed up on www.alldatadiy.com with (4L60E). Hope fully, they will be that good on the older 700's!

ZaphodB

I think a good thing to test, just to find out what might be wrong would be to restore the 2-4 band back to stock - And see if things start to shift again.

Because I am getting more and more convinced that the gremlin is in the 2-4 servo/2-4 band.....

I have gone thru the valvebody 2-3 times, and everything looks fine, the only part I am uncertain of is that ****ing 2-4 servo assembly.

Yes, I have the parts in the right order, but I have the feeling that something just doesn't feel right!

On monday I am going to re-install the original 2-4 servo assembly to possibly rule out if this is the problem or not.

ArrioZ28

When you pull the servo back out, insert a crosstip screwdriver into 2-4 servo pin bore and check the band. Mark the scewdriver with tape or other, with the servo assembly length from pin tip to cap snapring land. This check is to ensure that the case anchore pin has not popped loose from the band and allowed the band to rotate away from the pin. If the case anchore pin is not secure, the band would move about 3/4 inch deeper than its suposed to.

In adition to that, for a test, carefully remove the two large o-rings (cap and center sleeve), scarf-cut teflon seal and the spring at the bottom of the servo. Then reinstall the assembly with cap. This is to more easily check the actual apply depth of the servo. Push in on the cap and it should easily bottom to the band. There should be about 1/8 inch from the cap to the snap ring retainer.
When completed, remove the servo and carefully reinstall the o-rings and teflon seal, also the bottom spring.

GMTech

The only thing I can think of is too much TV pressure, not enough Governer pressure, or a gross leak somewhere. The TransGo throttle valve is amost impossible to get stuck in the MAX position, and I'm sure you looked at it and compared it operation to what was in the video, right? As far as the governer, it seems unlikely that something would happen to the governer, since you didn't take it out and it was shifting before the install kit, but it probably wouldn't hurt to take it out and make sure the gear is OK and the valve inside the governer moves freely.

Something I have seen a few do, and almost did myself a few times is the piston pin for the 3-4 accumulator. Do you remember seeing it in the case when you put the spacer plate and valvebody back in? The pin just pushes into the case and can fall out into the drain pan when your not looking. Theoreticly, it should only effect 4th gear, but you never know, just one more thing to possibly rule out.

Have you taken the servo back out and inspected it? There should be two teflon sealing rings on the 2nd piston, a red o-ring on the 2nd housing and a teflon sealing ring on the 4th piston.

How fast have you tried driving the car to try and get third gear? If you haven't already, run it up to redline and let off, most 700's will skip into 3rd between 20-30 MPH at minimum throttle.

white89_350

I have a 6000rpm rev limit. I drove around and hit the limiter 3 or 4 times to force it to shift. It did not shift into 3rd ever.


I will wait for Zaphodb to replace the old 2-4 servo and take a test spin before I do anything else. I will try and talk to transgo about this on monday afternoon.

ZaphodB

My car works okay now with all gears.

It was not the 2-4 servo, it seems that most likely it was a stuck valve in the valve body.

I took it all apart and cleaned everything, including the valves that I did not replace and after putting everything back together the tranny works!

I'd like to thank everyone who helped me with suggestions & ideas for troubleshooting my tranny, and hope this thread will help others who have similar problems...

white89_350

That is what I was thinking but wanted confirmation instead of just taking off the valve body. Did you find any in particular(valves) that were stuck?

I called TRANSGO and Glen would not answer any questions until I check the pressure first.

ZaphodB

If you look at the valvebody with the TV valve to the top, check the valves on the left side (The side where you don't replace any valves).

Check that all of them moves freely with a small screwdriver.

Talking about checking pressure on the tranny, what tools/connections would I need if I would want to check the pressure of the different parts of the tranny, could be good to know even though I have no immediate need for it right now.

ArrioZ28

Thats great!!
Glad that you got it working. This has turned into a rather long thread, but it has a bunch of great info in it for those to follow. Again, congratulations on your success.

BTW, how do you like the shift performance now?

GMTech

Outstanding! Glad you got it figured out! Do you think maybe it was a metal shaving from when you drilled the holes out? When I do TransGo kits, I completely dissasemble the entire valvebody, then do my modifications, flush the bare body, then re-assemble with the "new" srpings and valves that come in the kit.

I bet you learned alot out of this whole ordeal! Now if we can only get white89's ride going again.

JP84Z430HP

Ya know, GMTech is probably right on with that. I bet it was a metal shaving or something. That just reminds me of the three rules of transmissions: 1. Clean, 2. Clean, 3. Clean!!!

I need to get started on putting my 700 together for my car. I have a feeling that it's not gonna last long behind the 355 that I just puyt in it over the weekend

white89_350

I'm goinna take mine out and use an entire can of carb cleaner on mine and make sure all valves are free! If that don't work I'll do the pressure check and recall Transgo with the results

ZaphodB

Much better..... Too bad that we have gotten some of the snow back again, so I'll have to wait until it disappears again before I can really try it out, but it feels alright now. And much better than before...

I guess the lesson learned is that even parts that you haven't touched needs to be checked when you don't find the problem by checking just what you touched.

ZaphodB

I don't think it was a metal shaving, but you never know.

But to be sure I gave the tranny a fresh batch of oil, because after disassembling the pan/vb 3-4 times I think there may be dirt in the old oil....

It was a valuable lesson learned, and hopefully others will have use of this thread when they get into problems too.

Hopefully white89's got the same problem as I did, as he did see the same problems...

white89_350

Car work will have to wait until warmer weather so I will know if I have the same problem later.

white89_350

I took off the valve body and cleaned it out with brake cleaner. Rechecked every thing from the video. Put it all back together and still no 2nd, 3rd, or OD.

ZaphodB

Did you check that all of the valves moved freely, even the ones that you didn't replace?

Use a small screwdriver and gently try to move the valves, if all move freely, it should work.

That was the last part i did after cleaning mine, and that worked after putting it together.

white89_350

Ya I remember that you moved all the pistons manually with a screw driver and did it myself about 3 or 4 times each. That did not seem to help. I wonder if the two gaskets can move out of place just enough to stop flow of the fluid? That is my only other guess. Before I get this done profesionally I will check the gov. gear that has got to be the only thing I can do anyway.

adonis710

i am having the same problem these guys had with the transgo kit. ive got reverse neutral and 1st. but one thing i dont think was mentioned is that once i get the rpms up and let off the gas its as if the car is in neutral but its not. if i try to go again the engine revs but nothing happens unless i take it out of gear and put it back. it made me nervous cause it felt like major slipping but there where no odd noises and the trans was working perfect before.

they mention that the pressure reg valve c clip should be in the second groove. well mine is but it just didnt feel right when i did it and the valve barely moves up and down. i guess it must be right since i couldnt get the clip to sit in the other groove.
can someone who has put one of these together tell me which 3-2 piston is normally used in the type 2 vb. i used the smaller one but on a different post i saw this...

"A few months ago I posted that after the performance shift kit from Transgo I put in the auto transmission would not shift out of 1st gear. After several posts and no problem solved by me or anyone on the board I had the car towed to the tranny shop. It turns out Transgo give you 2 pistons to choose from in one of the bores. Transgo did not say which was best so I guessed the shorter piston and it will cause the gov gear to flood and not shift.

Use the longer piston when you do the shift kit from Transgo. This is costing me way too much money now for there oversight. "

im pretty sure the larger one was too big to fit but maybe it does.

also i now realize that i forgot to take that extra thin washer out before my final installation of the servo but the band was moving freely.

I do know one thing for sure. This Sucks!!

ArrioZ28

This may be unrelated to your issue. But it something you could check.
If your 7004r has the TV linkages that has a pin that pokes through the valve body and displaces a large checkball, it is important to have the TV cable adjust properly before the test drive. I had an occation where a friend installed a unit I built and he said it would not shift out of first. He had an aftermarket carb and linkage, so he just left the TV cable loose. The large check ball that the TV linkage pin unseats is a safty device that blocks TV exhaust and builds high TV presure preventing upshift. This is so that if the TV cable breaks or becomes diconected you won't burn up the trans with low line presure. Some folks just leave the ball out when installing the balve body, but you would be bypassing a safty device.
Usually the trans would upshift one time after a restart or cycle back to nuetral/park. But after that, the TV presure would be too high to allow an ushift out of first. You should check the linkage at the valve body to verify that it is moving and unseating the ball just as the throttle is opening. Also if the the linkage has no pin and you have installed a checkball there, then you will have no upshift.
Hope I explained it clear enough.
Good luck...

adonis710

i did not reinstall the copper checkball

look at this post, i have something leftover that looks like that. could that cause it to not shift?

https://www.thirdgen.org/forums/tran...shift-kit.html

adonis710

these are a few things left over.

there are two check *****. the copper colored plastic one that came with the kit and a metal one from the trans. They are the same size and larger than all others. i used all ***** that the video and instructions called for.

the two rings are from the old filter.
the orange one came out with it but when i tried to put the new filter in it wasnt going in far enough so i pulled it back out to discover another ring stuck to the end. i guess whoever changed the fluid before me left the original in there cause it looks the same as the new one. im hoping it wasnt supposed to stay in there.

i cant remember where the rod on the left came from. i thought it was just a part that the kit had me replace but maybe its not.

ArrioZ28

That rod/pin is a seriouse part. As referanced in the post you have a link to, it apears to be the accumulator piston pin fron the case. That pin, left to themselves without the valvebody plate to hold them in, they tend to just fall out.
The o-ring and orange seal are no biggy. Just leftover stuff from the old filters. Just as long as there was one on the new filter you installed.
Not sure about the check *****. May be extras not needed for a particular setup, like street/towing/race.
Reinstall the servo pin into the case and try it again.

ArrioZ28

A common checkball to miss is the one in the auxilary valve body, or the one at the rear of the case for the low-reverse. The low-reverse ball is suposed to be capured by a couple small metal tabs to keep it in place. Sometimes the tabs get a little beatup and don't hold in the ball. The aux valve body, the long aluminum one to the rear of the cast iron valve body, has a check ball under it.