Transmission won't go in reverse.

[Sixpack_Sid]

I rebuilt my 727 trans last year and put in a trans go shift kit in it. I bought a 440 from a motor home with trans I switched the tail housing when I had it all apart. I also put a sidewinder shifter in it. So now I got the car all assembled and ready for a test ride. It moved forward about 4 feet then I tried reverse and nothing. Any ideas of what to look for?


Thanks

Sid

 

[Lefty71]

Well, for sure you are going to want to look at linkage first (carefully ). And also check the fluid level after shifting into each gear, and make sure to check in neutral. Any foaming, or weird noises to report??

 

[AJ/FormS]

More as to what @Lefty71 said;
If the manual valve is not on the detent, but is stuck or positioned between gears, it will act like a huge fluid dump back into the pan.
This can happen;
thru misadjustment of the shifter, OR,
thru an incorrectly sized external shift lever, OR
the internal shift lever having dropped down, out of engagement.

But If it turns out that those are all OK;
Reverse works by applying fluid pressure to the L/R band, AND simultaneously, to the High-Drum, which Chrysler calls the Front clutch.
So, After the basics are done, regarding the mechanical linkages, and it still does not work, the best thing to do is run a pressure test, to see if the hydraulics are working.

 

[Oldmanmopar]

Check the reverse band strut. Do you have low in 1 position. and 1st in drive position. I believe they are applied differently.. That is why when racing with a full auto you should launch in drive and pull to low once moving.

Those with full autos try it you will see a big difference on the shift. No overflap

 

[Bewy]

I have installed many Transgo kits, but that was many years ago. Unless they have changed the design, the kit includes a much stronger L/R servo spring. I have had the pressed steel spring retainer pop out under the extra spring pressure. Result is no rev or manual low. The real problem is the retaining circlip; it is too flimsy & the groove in the housing is not deep enough.

 

[KickDown]

I'll agree with Bewy 100% on this. Due to the stronger Low/Reverse Servo Piston Return Spring supplied with the TransGo reprogramming kit & the increased internal apply pressures after installation of the reprogramming kit, I always use a billet aluminium Rear Servo Spring Retainer.
The photo below shows what can happen if the stock spring retainer is used. When this happens, Reverse gear leaves the building!
Billet aluminium retainers are available from A&A Transmissions for 30 Bucks Part Number AA296AR