Just when I start, once going it seems to be ok. I am going to get by tranny fluid changed once everything is open. Anybody else have this happen.
07 xkr

 

Canadacat,
Interestingly I've noticed the same thing in my 2009 XKR, occurring occasionally when I accelerate immediately following a stop or near stop (e.g. a rolling or brief stop at a stop sign). Coming out of the stop, the transmission slams into first gear with a jolt. I've only had the car less than a month, but the issue first appeared a couple of weeks ago and seems like it might be getting worse. However, the issue occurs infrequently so it is difficult to tell for sure. I am still in the "watchful waiting" phase but if it persists I will bring it in to be checked out.

 

Feels like a universal joint going

 

You are describing the "type 2" lurch exactly.
You you can search The forum for lurch or even Google it and you will find tons of information.
The type 1 lurch is when you come to a rolling stop
And it downshifts hard into first.
Many different opinions (from transmission fluid to valve body/solenoid) but most agree that it is a software issue. Driving habits affect it greatly.
Especially noticeable in stop-and-go traffic.

search for "ZF lurch". It is a ZF issue not a jaguar. Other luxury cars that use the same transmission suffer from the same issue.

 

Much thanks Canadacat and Kongo1!
-Marlon

 

Typically U-Joints issues reveal themselves when shifting from park to drive or drive to reverse, you will hear and feel a clunk, but not on acceleration from stop to start. On acceleration you might feel vibration under the car. I believe your problem is elsewhere, but if you're inclined to get under the car, U-joints are easy to inspect and easy to replace.

 

I get this sometimes too. I just manually shift down from 2 to 1 if needed.

Or in stop n go traffic I will keep it in sport mode so it stays in 2nd gear. Less wear on the tranny and you can move perfectly fine from 2nd gear.

 

In automatic operation the transmission normally starts from a stop in second gear anyway, so you are not doing anything that ZF didn't already plan!

 

No, it only goes down to 2nd when the flappy paddles have been used and the driver has forgotten to downshift. In full automatic, it does go down to first gear. Every time.

 

+1 What everyone else said.

This is usually the telltale time where I perform a full system reset. And following the battery reconnection, perform a regimented process of having the car 'learning' my driving habits all over again.
It may not accomplish much but it is a good excuse for a spirited drive.

As all the longer term members know, I like the paddles. But again there is a proper way, and improper way to use them. (I'm agreeing with you @Cee Jay

Cheers All!

 

It might be worth checking the fuel trims are sane, as an air leak can cause a bad gear change - obviously at a time of low revs when such a leak can have a big effect.

NOTE: if you've had the battery off you need to let the OBD monitors set and the trims have time to relearn i.e. stabilise. They start at zero on a hard reset.

Particularly look at the trims at idle with a hot engine.

 

Mine is not an issue down shifting it is from a dead stop. It acts like it slips for a half second then jolts into gear
No other time does this appear to happen

 

In every vehicle where I've experienced the above symptom, it has always been either low fluid or a worn band. Probably the worn band BECAUSE of low fluid, but that's the chicken/egg deal.

 

The "type 2" lurch that I refer to happens when you almost come to a stop but then decide to accelerate, you will feel a slight hesitation and then a thump into gear.
The "type 1" is when rolling to a stop and feeling as if you got a little thump in the back. It can vary from just feeling the downshift to feeling like you got bumped in the back. Some cars will experience both, some only one or the other, and some will never experience either.
​​​​​​ I'm not insinuating that this is definitely what you're experiencing only offering a potential possibility.
Again, Google "the ZF lurch theory" and you can decide if you are experiencing something similar.
​​​​

 

I took the suggestions to use Sport mode and paddles to avoid the Type 2 lurches I was experiencing. Although I have experience with driving manual transmissions, I never utilized paddles before, even on my cars that had them. It took me a little while to get a feel for shifting - definitely was overthinking at first and was often a little late in shifting. Once I stopped staring at the tachometer and trying to time it just right, shifting became smooth and seamless. After a few days of Sport driving, I went back to full automatic. Perhaps I have just developed a better feel for the car (I've only had it a month), or perhaps I'm just being more careful to come to a complete stop before accelerating, but I have not experienced the dreaded lurch since resuming full automatic mode. I suspect this is due to my change in driving habits, but is there a possibility that the adaptive transmission software "relearned" my driving habits during Sport mode and overcame whatever was causing the lurching? I know it is unlikely that the adaptive software is active at all during Sport mode, so I am "just throwing out ideas" here. (Based on what I heard on the news this morning, I feel the need to distance myself from the "idea" thrown out by President Trump of ingesting disinfectants as a possible treatment for COVID-19 - if anyone is tempted to try this, please don't....) Thanks.

 

No need to look at the tach. 'feel' the acceleration and 'effort' by the engine. she will tell you when to shift.
That engine 'likes' to rev. Let it live a little. DON'T CHANGE THE GEARS at 2000 rpm! (an annoyance with little boys and there 2 or 3 series bmws)
Reminds me, my father taught me the red line WAS the shift indicator. Those were the days...

Cheers All!

 

Deleted: Wrong thread.

 

Brutal has changed the pan and filter on both my old XJ and the current XKR with no ill effects. This is not a flush, just change the oil in the pan, oil in the cooler and torque converter remain in place.

Did your indie use a flushing machine on your car? This can be bad news as these machines usually retain some oil from previous flushes in them and this gets into your transmission along with any dirt or other crap that may be in the machine. One other thought, perhaps your transmission is just over full.

 

Couple of points.
A bad u-joint will make itself known when you're idling across a parking lot at low speed, foot OFF the gas, as the drivetrain loads up, then unloads, clunk, clunk clunk.

My first "major" "road repair" was doing a U-joint replacement on a 1964 GTO in the parking lot of an auto repair store with both the joint and a hydraulic press...

I'm a new XK8 owner but the symptoms described wound IDENTICAL to me to the "cracked drum" I was warned about on this vehicle, occuring with regularity to the ZF transmission somewhere between 50,000 and 125,000 miles. Hesitancy, clunk, etc. that's the XK8, ZF 5 speed, Not the 6 speed in XKR...nevermind!

I concur that over my LIFETIME the vehicles that clunked a little / takeoff hesitancy (feeling a lot like a higher stall speed on the torque converter) have OFTEN been a half-quart low on transmission fluid; all but the Chevrolet 1997 K1500 (& nearby models) which wore the too-small output shaft & insuffcient # of splines on the output shaft of the tranny; greasing with HEAVY grease will make it go away...for a while.

Cheers!

 

I have the same problem with my 2003 XK8. I drive it less than 1,000 miles a year. It only has 25,000 miles on it and I've noticed it since I bought it four years ago. In my case, the jolt after a slow rolling stop can be really bad. The engine will briefly speed up as I step on the gas while still barely moving and then will engage with a real kick. For a moment it seems the engine and transmission aren't connected. It also seems that if I come to a dead stop there is no problem. It's the worst when I pull into my driveway which is on an incline and let off the gas for a second. When the car stops moving or maybe starts to roll back a bit and I step on the gas there is a really big kick as the engine speeds up for a half second and then engages. I took it to a transmission shop and unbelievably the jolt was gone during the test drive and there were no transmission or engine codes. So after reading many very interesting and informative posts on this problem and many suggestions on the possible causes I just have one question. Has anyone out there done something that has truly fixed the problem? If so I'd like to hear it.