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Identify this Transmission??? Can it be made to work in my 1999 GTP?

Shmoke

New member
I have a brand new transmission that appears to be from a 2005 GP. The Yellow colored data tag has the following info:

615CGB and W016P

GM P/N 24229076

Here's where it gets interesting... I want to put this trans in my 1999 GTP. I suspect that this is a Tap-Shift tranny from the brief info that I can find on Google but I think it still has 2.93 final drive.

I have a 2003 PCM and DHP PowerTuner for any differences that I encounter with gearing but will a tapshift trans work with a non-tapshift PCM?

I understand that there are valvebody differences with tapshift tranny's, how will they effect operation in my case?

Will the stock 1999 wiring harness be adequate to connect a 2003 PCM with a 2005 trans?

I also know that the cooler lines will not be compatible. Can I remedy that by buying cooler lines for a 2005? Maybe I can make an adapter on the lathe?

This trans has been put away dry for seven years now. How should I best wake up the beast? I know that all of the seals and clutches were installed with some fluid on them but is there any way to ensure that everything goes fine on start-up?

Thanks very much in advance for your help!
 


Learned something new.

This Trans has all seven detents: P-R-N-D-?-?-?. Does that indicate that this is NOT a tapshift trans? Or do they use the same 7-detent manual selector shaft/cam between the two models?

What would a TapShift trans do if it were manually selected below the "M" range?

Is there any way - besides the data plate - to identify this transmission? Can a TapShift Trans be easily identified from the outside somehow?

I hope this is not a TapShift trans and that simple changes could make it work with my setup.
 
Look at the info on TripleEdgePerformance.com all the info to ID the trans should be there.

If you are a 99, you should have click style lines. Which means the lines should be fine. You will need to move your external pnp switch over
Reference this on how to align the dot to the line only. Your car will have the wiring needed, as you currently have a switch on your trans.
http://www.grandprixforums.net/how-add-external-range-pnp-switch-transmission-49297.html
 
So that 2005 Transmission is INSTALLED in my 1999 GTP. The trans has the quick-connect fittings and my stock 99' cooler lines are the threaded type - so they are not compatible without some adaptation. Can I use 2003 cooler lines to link this trans to my stock radiator on my model? How about 2005 lines? They are much cheaper but look a little different. What is the difference?

How can I connect my 1999 radiator/cooler with my 2005 trans without breaking the bank?

BillBoost37: Thanks for the install advice for the external shift switch - I placed it perfectly on the first try. No problems. THANKS!
 
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There is a year with quick at the trans and threaded at the radiator. I am not sure which year..but look through. Or modify yours. Either way.. it can be done.

Now..on the wiring. IIRC the newer years have to have two pins swapped. I know that it's posted at NEPontiac.org and I linked it at GMForums.com. Can't get to either from my location but I want to say two pins had to be swapped something like N and S ...I'm not 100% positive. though.

Looking at the trans connector pinouts for both years (trans and car) should make it obvious
 
Now here's something interesting...this supposed Tap-Shift trans can be manually shifted in the three lower gear selections just like a normal 4T65E. I wasn't expecting that. Studying the hydraulic schematic has lead me to believe that shifting into 2 or 1 would dump line pressure to exhaust and drop the trans out of gear. It just works like normal.

Weird.
 


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