Hey, new to forum, but loved Jags forever.

Just bought a 1995 XJ6 with 100k. Car is in great shape. I live in Wisconsin, but bought the car in Atlanta. I flew in, got the car, had the oil changed in Atlanta and drove it straight though to WI and it was perfect. I brought it home, changed air filter and plugs and it idles and runs great and smooth. However I have noticed a shudder at 50 MPH sometimes. Seems to happen more so when I am getting on the gas pedal. Everything shifts very smooth and runs very smooth (so very, very smooth) however sometimes I will get this shudder and when I look down it is exactly at 50MPH. Does not do it at any other time.

The tranny fluid is light red (Not deep red like it should be), but not dirty or burnt. I am taking it in to have the tranny flushed and replaced with new Dexron III, and I am hoping that will solve it. However does anyone else have any advise? I am hoping to run this car for many more miles, and I am obsessive about maintenance. Everything is perfect except this shudder and it drives me crazy to think there could be a problem with the transmission.

Any other experiences with this would be great.

 

Sorry its a 1996 XJ6

 

My first thought is that you're feeling the lock-up torque converter. At steady speed and light throttle the torque converter will be "locked" until you hit the brake or apply throttle...when it will unlock.

Sometimes, if the road speed, engine rpm, and engine load are "just so"...and 50 mph is a typical point as far as road speed goes....the unlocking event will give a shudder.

Fresh fluid might help soften it a bit...or might not. Personally I woudn't worry about it if it lasts for just a moment. Mine does it from time to time. It really isn't all that unusual.

If the shuddering lasts for more than a moment it might be a peoblem.

The other possibilty is an engine misfire. For a brief instant before the converter unlocks but while you apply throttle the engine load is increased... as in a car with a stick shift where you get lazy and stay in a too-high gear while accelerating. If there's a small ignition fault this moment of increased load will be where it shows up.

Others will chime in

Cheers
DD

 

Thanxs Doug,

I was hoping someone would chime in as "this is normal" or "Try This" I am handy with anything with an engine be it may harley, my tractor, or my Montero with 215K miles and running great.

I know this is most likely the TC I am feeling, and it does not happen all the time, but it has happened about 5 times. I have only owned the car since Saturday, and the first time I noticed it was with the Sport Mode on showing my wife what the car has. However now that I am tuned in to it I notice it anytime it happens. It is dead on at 50MPH, and I notice if I drive like an old man, (which I normally do) its smooth as silk, but when I want to hit the gas I will feel the shudder sometimes. It lasts for 1 second and no more, but I feel it clear as day. It definately happens during shift (2nd to 3rd?) because as stated I am usually getting on the gas and raising the RPM's when it happens. All other shifts seem great.

Thanks for the input.

 

Hard to say without driving the car myself, however...if the problem resides in the autobox, the first thing any mechanic will tell you is "get as much of the old ATF fluid drained out as possible and replace with new". There has been much discussion on this website about the ZF autoboxes being 'sealed for life'. The general conclusion here is that they are no different than previous boxes that were provided with filler caps and dipsticks.
Now I don't know what autobox is fitted in your car, but a few cars back I had the same model and year as yours, and it had a ZF SIX-speed autobox. Someone told me this, as I thought it was a 5-speeder, until the slight jerk I got passing 55mph. was a changeup to 6th gear, so I was informed.
Anyhow, If the car's done more than 50,000mile, CHANGE THE ATF FLUID. You can use an additive at the same time if the car's a high-miler. The best tranny-fluid change is via the cooler lines as it gets rid of the fluid in the torque converter completely, but those machines the garages use cost money. It's no good looking at the fluid or smelling it, old fluid has a poorer viscosity index, and the additive package will be depleted, no matter how nice it looks. No ATF fluid is going to last forever, and it's under a lot of stress from the impellor blade tips. If the previous driver has booted it some, then ATF should be changed at 30,000mile. The shudder you're getting could be early signs of clutchpack judder/shudder, as well as possibly the lockup clutch in the torque converter. This sliding clutch can be operated in an in-out-in-out fashion at certain speeds, to 'soften' its effect. It depends on the design of the control software. A juddering clutchpack is often caused by glaze on the frictionplate surfaces, a high miler condition, but as a rule, this happens during lower gear changes with plenty power on. See how it is after new fluid and the additive. You'll need to drive it 500mile or so to get full effect.
Leedsman.

 

The XJ6/X300 with the 4.0 L six cylinder used the 4-speed ZF4HP24 transmission. It is not the sealed-for-life type.

The 5 and 6 speed ZFs came later...with the 8 cylinder cars


Cheers
DD

 

My XJ6 was a 3.2litre engine, and there were most def SIX shifts, my son and I counted them on the motorway more than once to be sure. Sorry! BTW., the alternative engine was a 4.2litre, hard to find s/h here as people wouldn't part with them. It was much more powerful and the same mpg. This was a partic. good engine, NOT the Nickasil one that came later with all its sulphur in the petrol problems.
Leedsman.

 

No need to apolgize. This is easily clarfied.


Jaguar sales brochures say the XJ6 came with a 4-speed automatic:
http://www.jag-lovers.org/brochures/...geusa995_7.jpg


Any number of internet auto sites, such as below, confirm that
http://consumerguideauto.howstuffwor...j-series-6.htm

The Jaguar service manual, which I just now looked at, refers to the ZF transmissions as "a four speed epicyclic drivetrain" . The spec section shows the ratios as 1st 2.48 2nd 1.48 3rd 1.00 4th .73 Reverse 2.09

Conspicuously absent from the spec page in the repair manual is any reference to 5th or 6th ratios.

The locking/unlocking of the torque converter can easily be mistaken for a gear change.

Cheers
DD

 

Try this for the 1996 Jaguar sales literature. The above link won't work.

http://www.jag-lovers.org/brochures/...-10-01-96.html

Cheers
DD

 

THanks to all for the great information. I just ordered my tranny filter and pan gasket and am having the tranny fluid flushed out by a good garage. We will go from there. I will post back on the results so maybe the info will help others.