No reverse, tires spin forward on reverse

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J

josekh7

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I have no reverse , all gears seem to be working perfectly . I disconnected my shifter and pull the shift cable by hand when I out it in reverse while the car is on Jacks the tire spin forward . . Could this be a bad servo ? Please help . . 727 with a transgo shift kit
 
Band,

pull the pan and look, it's the easiest way
 
You said one tire.
This may be normal if the other side is locked

The fact that the tire rotates at all, tells me that the clutch and band involved are in fact working. Since "all forward gears are working" tells me that all the clutches are working and the 2nd gear band too. Manual low is supposed to engage the L/R band , but if the band does not grab the drum, then it will still drive forward thru the sprag.
I think your L/R band is way out of adjustment or damaged. There is only one way to tell, and brian6 nailed it.IMO
 
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the rear diff will make it go the other way, if it is upside down, happens when folks install a truck rear in a car
 
I drive the car and it works fine going forward , so if I pull the land what should I look for if it's the band ? I know that a rear servo would be damaged or cracked have no idea what a bad band looks like or jf just out of alignment
 
How well does the 3rd gear clutch hold?
See, in reverse,the L/R band and the Hi-drum are engaged.
In manual low, it's the L/R band and forward clutch.
In 3rd/Hi, the hi-drum and Forward clutch again.
In 2nd it's the KD band and the forward clutch.

So to be driving forward in selector lever Reverse, It would seem the hi-drum is not engaging, and that would lead to a faulty Drive power transmission.It could also be that the forward clutch is jammed up. Then reverse with a slipping hi-drum,is the same as manual low. And if the forward clutch is jammed up, the forward gears might all still work fine, as long as the forward clutch stays locked on.
If the L/R band fails to apply, then reverse would fail completely, but manual low would still work through the sprag and you might never know the band was done, except for the no-reverse action.
So that leads to the question; how is it in drive, will the hi-drum accept full power. If yes, then I would suspect a jammed up forward clutch, or a faulty valve body, and that could be proven with an air-pressure test. Well not really; the pressure test will prove the clutches and servos are or are-not working. If they are working properly, then by process of elimination, the issue has to be in the VB.
At least that's my thinking.
So If the road test proves the hi-drum is working, and no Neutral-creep,I would be doing an air-pressure test,followed by a band adjustment, probably a second air-test, and finally, probably a VB inspection.
 
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Ya I have had the direct or forward clutch weld itself up that would do it, does it feel like it's binding up or does it spin free, if you are lucky it could be the apply rod fell off (not adjusted right) or the band just fell apart. Look for a lot of material in the pan.
 
Oh ya, you guys from Canada can take back your cold weather we have had enough single digit temps!
 
If the Foreward clutch is dragging or welded, it will want to move fwd in neutral and reverse. Had a 904 weld the forward clutch from a kickdown cable that came undone. Smoked the fwd clutch shut.
 
With the wheels in the air acting like the car wants to go forward when the trans is put in reverse is the rear servo not holding the rear drum, or it's low on fluid.
 
AJ/FormS said:
Hasn't really been cold here yet. I think it was about -31C one morning. I think that converts to -24F. Time to put a hat on tho....that's only cold when the wind blows
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Your tougher than I am!
 
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