Folks, I am a recent Discovery owner and Jeep world crossover, and so far love it... with one exception. I am having a problem with the transmission shift points, and could use some help and advice. First of all, the vehicle is a 98 Discovery 1 with 82K on the clock, 4.0V8 ZF auto trans. First to second shifts where I would expect it to, but I have to hit 3000 rpm in order to shift from 2 - 3 and again from 3 - 4. Is this normal ? It feels like it's on the high side, but what do I know. In poking around I found that the kickdown cable was disconnected from the TB butterfly, so I connected it back up and adjusted it per the RAVE manual and..... it made the problem worse. With the kickdown cable attached properly, the shift points for 2-3 and 3-4 transitions were over 3500rpm. So, I disconnected it again, thinking that the previous owner was already one step ahead of me on this. Fluid is fresh Dexron and set to the correct level per the RAVE manual. Any thoughts and advice on what the normal shift points should be and how I might migrate there would be most appreciated. Thanks !!

 

Not normal. When the tranny is in good condition you wouldn't even notice the shift points except when the torque converter locks between 3rd and 4th. It's not even perceptible during normal driving. Did you adjust the kick-down on the tranny? It's in the Rave. What did you find in the drain pan when you changed the fluid? Clutch packs rarely if ever fail so that isn't the problem. Governors do stick. Drop the pan, change the filter and adjust the kick-down on the tranny per the Rave then report back. Your mileage is too low to say it's a tranny failure yet unless the fluid was never changed and sat for long periods.

 

I had the exact same issue when my kickdown was disconnected. when I reconnected it, I gave it a bit more slack contrary to the instructions of the RAVE. When the TB is in its home position loosen the kickdown cable a little. My cable is far from tight. there is about 1/4 inch of play at rest. You can also pull back or tighten slack on the tranny itself. I shift normally now but from what I can tell, I still need to stay aware how im depressing and releasing the gas pedal so the trans can kickdown correctly (ease off a bit when its time to shift). Crap plugs and wires can cause some extra bog on the engine too thus making you give it more gas than needed and perhaps throwing off the relative shift points. If the ignition is all pretty and cared for your engine wont have to work as hard at higher RPMs.
OH YEAH AND CLEAN YOUR THROTTLE BODY!! ITS HELPS ACCELERATION (PERHAPS SHIFTING TOO)!!!

Any Corrections to my advice is more than welcomed.

ROVER ON!!
BRIAN

1996 DISCO SD
179K
New trans, 235/75/16 Hancook ATM, 20K service done yearly. Lucas gear oils and oil treatment.
Onboard Bluetooth OBD2 scanner for all live data.
Save a disco=buy a scangauge

 

thanks for the replies ! So far I have taken the lazy man's way and have done a series of partial trans fluid changes via the bung as I haven't yet had the time or motivation to grow a set and drop the crossmember and Y-pipe to get at the filter. But the old fluid coming out didn't look terribly nasty or suspicious. Dropping the pan is on the list, I guess clearing a day to do it has to get on the list too. I adjusted the kickdown cable both as indicated in the RAVE manual and also as you recommended with the same effect - it makes the problem worse and instead of shifting at 3k it shifts at 3500+ with the kickdown cable connected in any configuration. Another fun fact - I tried adding some of that Lucas trans fix (stops hard shifting, they say so) stuff during one of my fluid changeouts thinking that a thicker fluid would raise pressure at a lower rpm but it did nothing, if anything it made it stay in gear just a hair longer.