i have an 85 xj6 on which the reverse went out yesterday, the day before the reverse worked but struggled before this i hadn't noticed any problem.
it has been suggested to me this could just need an adjustment to the rear band? is this true or are they pulling my leg? if it is true, how can i do this?

 

A band adjustment can do NO harm.

The 2 locknuted crews on the outside of the transmission, one on the RH side, the other on the LH side, and it has been a loooooong time since I have done one, and I simply cannot remember the exact location of the RH side adjuster, but the LH one is via a panel in the tunnel of the car, which is accessed under the carpet, and a screwed on panel removed. Even then it is awkward, due to linkage arms in the way.

I do the adjustment be unlocking the locknut, turning the screw in so it just "snugs up", then back it out 3/4 turn, lock it up.

I would also be checking the trans fluid level, engine running, hot, would be my first suggestion, if you have not already done so.

The adjustment of the actual select cable would be a smart check also, coz the lever inside the car may be in the "R" position, BUT, is the transmission actually going into "R"??.

 

I agree, checking the fluid is first and foremost, could be low. Also the cable could be stretched. Eliminate those two first before you adjust anything.

 

transmission fluid is good have checked the cable adjustment it too is fine. i tried to locate the rear band adjustment from underneath the car had no luck but to be fair was struggling to know where to look will attempt again the weekend and maybe look for an access hatch from inside car

 

One very happy camper lol. Adjusted the rear band on transmission and reverse is now working fine. The adjustment screw is accessible from under the right side of the car and indeed if you get low enough can actually be seen from side and someone with long arms may even be able to adjust it without lifting the car. it is located centrally directly above the transmission pan. In my case i had difficulty finding it because of all the accumulation around it. My friend that told me of this adjustment states that Jaguar recommend that both bands on this model should be checked for correct adjustment every 24,000 miles. the front band is accessible from driver side through access panel in transmission tunnel, found underneath carpet. the correct adjustment is tighten to 5lb ft, then back off 3/4 turn, No wonder my reverse didn't work i had to tighten it 2 full turns to get 5lb ft.

 

AH, got to luv a plan that comes together like this.

Another Jag out and about, SWEET.

Maintenance, such a wonderful thing, mmmmm.