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Discussion Starter · #1 ·
I recently installed the chevy part # 8673948.
It was an upshift valve that allows the camaro to shift from 3rd to 4th gear at wide open throttle.
After the install the car hesitates a long time before going into OD from park.When it does engage it does so very easily to the point of where you dont even feel it.All the other gears are engaging fine.
When driving the car and taking off in 3rd gear then while moving bumping it into OD it engages fine.Even when driving in OD and stomping the gas it down shifts and upshifts fine.

Can someone please help me?
I know absolutly nothing about trannys and should have left it alone.
 

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I'm not an automatic guy (I'm sure someone who is will chime in) But I wouldn't worry too much. This IS how we learn. You should be congratulated on your attempt. An automatic valve body is pretty intimidating to most mechanics (myself included) so don't feel bad.
I would remove or reverse what you did and test drive it. If all is well then read the instructions (hopefully they were in the box)or the service manual and reinstall it. You may have put something in backwards or upside down or both. I think as long as you don't get too far over your head you will be fine. Worst case scenario would be to have a tranny mechanic help you out, but you will have gained some knowledge.
Jim
 

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Did you also install the boost valve? Did you have any pictures to help with getting the upshift valve, sleeve, and spring in correctly?

I have installed this same kit at the same time I did a TransGo reprogramming kit.

It sounds like the valve assembly was either not installed correctly, or maybe not in the correct location.

I haven't tested the upshift at WOT portion yet, although I do know that once over 80 MPH it won't downshft at WOT


Bob.
 

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Discussion Starter · #4 ·
well the GM kit never came with any instructions so i kinda had to fly by the seat of my pants on this installation.I have never even seen the inside of a transmission untill this.I am an engine guy.

I installed the TV boost valve and an upshift valve (i believe thats what its called) and also the 2 gaskets that goes on the seperator plate and a new pan gasket.
I was sure to put the new parts in exactly as the old ones came out.
However the little ball bearings that lay on the seperator plate wanted to be a pain during the reassembly.I was thinking they might be the problem but i have no clue what they do.
 

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OK, I'll try and cover everything I can remember that can go wrong. The TV cable adjustment will need to be checked and possibly reset. R&R'ing the valve body will cause this.

The boost valve: There is a step in the bore that looks like where the snap ring goes, but isn't. The step is lower then the actual groove and will cause low line pressure. Typically the boost valve will then end up in the pan. The line pressure gets real low.

The check balls are important (the little ball bearings). I use petroleum jelly to hold them in place. I stick them into the case to avoid knocking them out of place as the separator plate goes into place.

The separator plate gaskets are different. There is a cutout, or a punched out, letter C on one and letter V one the other. The C one goes against the case, the V against the valve body (VB).

The upshift valve assembly is the only one with the D shape on the end of the sleeve. This is visable from the outside of the VB. There is a notch in the side of the sleeve where the roll pin holds it into the valve body. Don't recall the direction or the order of the valve and spring parts. With taking care to replace then as the old ones came out you should be OK here.

Don't know if you did a drain plug ot not, but they are great. Took me a couple of pan drops before I got tired of ATF flooding out of the pan all over. Drain plug went in, and nice, no mess.

The torque spec for the VB bolts is low, about 8 ft/lbs IIRC (96 in/lbs?). Then need to torques them in a circular pattern. Else leakage can occur. Same spec for pan bolts.

If you can put a pressure gauge on the tap, that may help to verify if the boost valve is still in place. Else just drop the pan and double check stuff.

If I had to SWAG it, I'd say either the TV isn't adjusted correctly, or the boost valve is not installed correctly.


Another one: if you replace the filter make sure to get the old gasket out of the bore. If two gaskets end up in the bore the pump will suck air and cause low line pressure and other problems.

As with you I too was a complete newbie with auto trannys. Sure, did a filter or two, but that was it. All through the install I kept telling myself that I should never had started into an auto transmission.

In the end it turned out OK. It all worked out.

Bob.
 

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Discussion Starter · #7 ·
Ok i think the problem is with the seperator gaskets.
I didnt know which was top or bottom.so i just matched them best i could by eyeballing them.
I havent had a plug put in it yet but im definatly getting one before the reassembly.
I tore back into it today and started checking stuff.
thus far i am just beyond the pan.
I can see the boost valve and it looks fine.
tomorrow i am going to go to the VB and seperator plate and check them.

I am glad i found this web site and would like to thank you guys for your info and help on this.

I will post more about this as i tear back into it.Stupid daylight savings time only permits me to work on the car for a couple hours a day.
 

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I'm not familiar with the part number. I'm guessing its a 4L60 of some type. Those transmissions, and others, will misbehave if their is air in the system. The hydraulics are made so they blead air out pretty well on their own. But the 4L60s were known to get air trapped in the 3rd and 4th gear clutches.

When I fill a transmissions, I dump in about 4-6 quarts and start the engine. Then I begin adding fluid until it's full. It's nice to know how much you need so you can get it close to the mark before topping it off a pint at a time. Next I cycle through the gears, forward and back, letting the speed get up to 30-50 MPH. Just be darn careful of who is around you. Make sure the vehicle is securely on jack stands with both rear wheels adequately off the ground. Before shifting between forward and reverse or park, be sure the wheels stop. If you have ABS, you may have to go to neutral before switching gears to get the rear wheels stopped.

If bleeding doesn't help, then drop the pan. A pressure test is a good idea. I don't think the separator gaskets matter. Top and bottom are the same - please correct me if I'm wrong.
 

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Discussion Starter · #9 ·
I got the car back together today and it seems the problem was with the boost valve.
I dont know what it was but i pulled it out and looked at everything and put it all back in.

After reassembly the car is running fine now.
the seperator gaskets were on wrong and i fixxed them as well.

I took the car out for a test drive and everything is running real good.

It does the WOT shift just as it should.

Anyways i have one more question for u guys.

I havent got the road in my area to rum my car to its top end.About the best you can get around here is 100-120mph then u run out of straightaways.

But heres my question.

Will a 1993 Z28 with the LT1 (newly rebuilt) and the 700r4 transmission actually do 150mph?
at 120mph the RMP's seem awfully high for the car to actually hit 150mph.
Would it be redlining if it can do 150mph?

My upgrades are:
K&N Cold Air Intake
New GM upshift valve and shift kit
Hypertech power chip (stage 2)
Catback Exhaust
Cat4ward Headers
Accel Fuel Injectors
MSD Ignition Coil
 

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On the backroads of W.Va., hmm. As for the top end question it would depend upon the rearend gear ratio. Also, did the TCC lockup yet? That too will affect the engine RPM at any speed. There are a bunch of gear-ratio/tire-diameter/RPM to MPH calculators on the net.

Glad to hear the trans is working.

Bob.
 

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Torque Convertor Clutch. When this locks the RPM will drop for the same MPH.

OTOH, maybe the TCC locked and the trans didn't upshift. That the locking of the TCC felt like the 3-4 upshift. In general the TCC will be forced to lock somewhere around 84-90 MPH. This is programmed into the ECM.

Bob.
 
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