hi: to summarize my prior post on this matter, put the 87 xj6 in drive and do just that with no problems. upon slowing for a stop, there is a noticeable clunk noise as the car slows to 10 mph (i believe this is when the trans shifts from 2nd to 1st). there is no noise during accelerating/gear up shifting.

here's the new bit of info: when i slow to under 30ish and i know the 10mph barrier is coming, i manually shift the "d" to "2" and i can cross the 10 mph threshold without a clunk......hmmmm......any thoughts??????

 

With your car sitting still and foot on the brake, shift into D and then into R and then back into D, all with engine at idle. Clunk? With or without clunk, I would check drive shaft for loose U-joints or center carrier bearing as well as transmission mount.

Dave

 

The old BW66 transmission was notorious for this clunk. And if your trans mounts and/or u-joints are worn, it'll be even more pronounced.

The fix is in adjusting the throttle valve/detent cable. This cable actually controls the operating pressures, and thus shift quality.

I'm sure there is many-years-old archived discussion on the adjustment....which must be made in minute increments.


Cheers
DD

 

yes, you are right (as usual) Doug. I too remember not only the discussion (which may have been on a different forum) but also that a very small adjustment to the cable immediately eliminated the annoying downshift thunk in the BW66 on my 1982 XJ6. But the precise details of the adjustment (easily done from the engine compartment, not under the car) escapes my pandemically faulty memory.

 

In theory, The inner cable is all way's the same length. It is the outer cable sleeve that causes the inner cable to raise or lower the shift valve. Shorten the sleeve to shorten the shift, lengthen the sleeve to lengthen the shift.
Practice on the cable brakes for your wife's bike. In order to keep track on the car, Draw a diagram with a arrow going left and right and write in the direction you go in case you decide you've gone too far. Don't use bread crumbs.

Larry Louton

 

Mine does this and stops doing it once fully warmed. Its a down shift from 3-1 while slowing to a stop during warm up. My current fix is to drive in 2 instead of Drive until I reach the freeway. The downshift from 2-1 is way smoother. I drive my 4.0 XJS in 3 instead of D also because I dislike the lack of instant go when blipping the gas and the car is in 4th gear. MPG is truly not an issue when driving these older Jags.