I am trying to diagnose a problem with my new trans.
I installed it, and the gear selector was off by a hair apprently...and the original tv cable had a mounting tab at the throttle bracket that was cracked.

I replaced the cable and adjusted it as per instructions from Bruce Toelle at PTS trans (they built the tranny).

The 1-2 upshift hangs...the engine will rev to the limiter unless i let off the gas momentarily, then it will go into 2nd.

This is an intermittant problem. When the trans is cold, it does shift and the quality is good, but it is still quite late.

I have had the pan down several times, there is no binding in the tv cable, linkage or valve. The fluid is clean and the filter is only showing residual traces of materials from the rebuild.

ALl other up/down shifts are perfect in quality, though are a tad late in the rpm range.

The 1-2 upshift hangs regardless of whether I leave it in Automatic or manually shift from lo-1 to lo-2 or leave it in lo-2.

I will be testing it with a hydraulic pressure gauge soon so i can monitor the line pressure at the point of the hanging...

The governor is stock for a GN, has the spring pinned so it doesn't fly out after a burn-out.

My trans specs and parts listing:

Trans Parts List

Any ideas on what it could be? Stuck check *****, accumilator..??

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Dan G.
87 Turbo Regal

 

I want to be clear on some details. You say it is an intermittant problem and then you say when it is cold it shifts (late but OK). Does this mean that the problem occurs when it is hot only? Does it only happen hot sometimes?

When this happens is it at any throttle position as in, you try to drive easy but it won't shift and you keep giving it gas until it hits max RPM's?

Hook up a gauge to the tap on the drivers side above the linkage. I like to record pressures in this way: All positions; idle, fast idle and fast idle with the TV cable pulled full (Fast/Max). It would be best if these reading could be done cold and hot. I take a piece of paper and make a row going from Park to Man 1, then I put lines down the paper with columns marked Idle, Fast, etc.

What I want to see the most though is the pressures when the problem is occuring. You will likely see one of two things and they will mean different things. One is that the pressure will be very high, as if you have the TV Cable pulled for the Fast/Max test. Or you will see normal pressures that vary with throttle position. The other thing I want to know is throttle response. When you step on the gas, the readings on the gauge should move as if you have a string attached to the gas pedal to the needle.

 

1. This occurs most frequently when the trans is hot.

2. Under progressive throttle, or usually anything beyond 1/3 throttle, it hangs in 1st gear and if i hold the throttle open, the engine will rev and cut out at the limiter...until i let off it momentarily...then it will haphazardly shift into 2nd

3. I will be getting a gauge this week to measure the pressure readings.

This tranny is a BRF th2004r, in a 87 Turbo Regal which is mostly stock.

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Dan G.
87 Turbo Regal
MODZ

 

Ok, I'll wait on the readings. I strongly recommend that you get a Snap-On pressure gauge. I have personally had the heads blow off of all of the other manufacturers gauges.

 

Possibly a burned band?

 

Any luck getting the readings yet?

 

Please explain a "burned band"?
Mine "hangs at high rpms. Shifts perfect lighter on the gas.
How can I cure that, too?
A Corvette servo & scuff the surface of the clutch pack drum for better grip?
CAN I JUST "ADD SOMETHING" TO HELP THIS, or do I need to drop the tranny?
I THINK, I can slip in a servo pack, up in the car, correct?
I was hoping to change the fluid to TYPE F FORD fluid, next fluid change to assist. I was told it has more "clutch grabbing" material in it.

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Chat Soon,
KED85
Karl
1985 Firebird 2.8 to 3.4 swap project for Smog Happy LA, CA

 

I will be purchasing a pressure gauge from my trans rebuiler, PTS, in CA on Monday.

So I'll have readings hopefully by the end of next week.

thanks for checking in.

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Dan G.
87 Turbo Regal
MODZ

 

Hi Ked 85. This post was about a 200-4R while you have a 700-R4.

Are you saying that it shifts late at high throttle? If so, a Vette Servo (do NOT scuff the drum) will not change timing, unless you are experiencing a slip that ends with a bump and therefore is FINISHING late (but started at correct time, just took too long).
You can try a heavier governor such as a normal V-8 governor and see if that is closer to what you are after. Get back with more details, perhaps a new post.

 

Ok!
Thanks for help me clarify this symptom.

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Chat Soon,
KED85
Karl
1985 Firebird 2.8 to 3.4 swap project for Smog Happy LA, CA