Harsh Shift

[ColoDisco]

First some specifics:

1995 Disco
Automatic transmission
Added 245 75 16 BFG MT KM2 tires
Welded on Sliders

Complete Transmission service done (including filter) at 180,000 miles currently vehicle is at 185,000 miles, added BG auto trans additive to
transmission and factory recommended trans fluid. All 3 differentials have
85w 145 synthetic valvoline as recommended over on LRF.

Drove to moab at the end of March towing my pop up camper. No problems going to moab, did alot of 4 wheeling while there. No problems. Drove back and had a tough time getting up Vail pass from the west side and up eisenhower tunnel from the west side. Drove fine for the next day after getting home then developed a really harsh shift.

Let me explain what this is like.

Take off from a stop-> vehicle shifts normal up to 2nd, revs up to almost 3500 before shifting into 3rd. Usually I let off the gas and it pauses then
BAM!!! slams into overdrive. Hit the gas and it downshifts back to 3rd just fine then have to let off the gas and BAM!!! slams into overdrive again. This happens over and over again. Will also happen if I slow down and it shifts down to 2nd then coast BAM!!! slams into 3rd and then again into overdrive.

Anyone else had this problem?

 

[mongosd2]

Did you flush the transmission or just replace drain and fluid? A complete flush and refill on a high mileage transmission is usually the kiss of death. Drain some fluid and let us know what color it is...

 

[ColoDisco]

Already checked that. The color is a darker red than when the fluid was new. Did not do a complete flush. Drained, replaced the trans filter and filled. The fluid smells a bit off as well.

Just a side note. I am a professional technician so I am familiar with transmissions. I work for Audi, am familiar with newer ZF transmissions, just not the Land Rover ZF.
Am I correct in assuming my trans code is ZF 4HP22?

 

[mongosd2]

yep 4hp22...worn clutch packs, new fluid=trans not happy.

 

[sven]

Another thing to check are the engine/transmission mounts.

 

[ColoDisco]

Another thing to check are the engine/transmission mounts.

Did check that. Found 1 of my engine mounts cracked pretty good. Not about to fall out but it is top priority. How would this cause harsh shift? Are you thinking torque of the trans shifting?

I forgot to mention it had this clunking noise before that turned out to be too thin of gear oil in the diffs. That sounded more like slop in the gears. Once I put in the 85 145 it went away. This definately feels like trans shifting concerns. I also had a CEL come on (code 48) which turned out to be an adjustment on the throttle valve due to me doing the head gaskets, I think I sealed up some old vacuum leaks when I reassembled the intake.

 

[mongosd2]

I think you know where this is headed...Call Marty for good used one:

Marty Powell
Giver of Last Rights to Fallen Rovers
270 576 7922

 

[ColoDisco]

I think you know where this is headed...Call Marty for good used one:

Marty Powell
Giver of Last Rights to Fallen Rovers
270 576 7922

I am more stubborn than that. I have to literally see it is a hopeless cause before I condemn it.

 

[Fivespddisco]

yep 4hp22...worn clutch packs, new fluid=trans not happy.

Agree my friend. We will not do the trany service anymore in the shop I high milage trucks.

 

[mongosd2]

actually happens more than anyone wants to admit with the high mileage trucks...after 100k, leave it alone, just keep it topped off

 

[evilfij]

ashcroft's website has some good advice on the subject.

I have heard of people cleaning out the valve bodies etc to save them, but never had to do so myself.

 

[ColoDisco]

What is ashcroft's website?

 

[mongosd2]

http://www.ashcroft-transmissions.co.uk/

 

[ColoDisco]

http://www.ashcroft-transmissions.co.uk/

Thanks! Reading now...

 

[ColoDisco]

I am beginning to think the kick down cable is most of my problem. It is broken and I have been limping it along since I did my head gaskets (bought a new one but have not installed it) because I need to do the cooler lines as well due to seepage at the pressure fittings. I think I need to start there. Problem I have is the trans worked just fine during my entire trip to moab including 4 wheeling. Guess it is because it is english.