Hi all,

The other day I went to pass a car and gave it just enough gas to downshift,far from flooring it, and on the downshift the transmission slipped. I let off the gas right away and it finally "caught" and I could proceed.
It has happened a couple time since. Up shifts seem fine. Another example is when i was going up a steep hill. The car needed to downshift and when it did it once again slipped. I let off the gas until it "caught" so I could get back on the gas again.
I bought the car 5 years ago with 55-60K mikes on it. I had the transmission oil and pan replaced when I bought it. The car now has 117K miles.
I have not heard much about these ZF transmissions having issues, so im kinda surprised. I stopped by my local shop to have them check the transmission fluid as I remember hearing these transmissions start doing odd things with low fluid levels. They said it was about a quart low and topped it off, however its still slipping.

Has anyone else had this issue? Thoughts or ideas from here?

Thanks!

-Trevor

 

Is it possible that it is still low on fluid? There is a specific procedure to fill to the correct level; maybe ask the shop what procedure they used?

 

The fill procedure is exacting and that means topping up is also - check it is followed exactly.

It's vital to use the right oil, too.

 

I would change the oil/pan/sleeve and pan screws NOW.
Sounds very much like low fluid level and that will kill the ZF.
.
.
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Thank you all for the info. I am unsure of the process the shop used to top off the fluid level or the type of fluid used.
There is an independent shop not far from me specializing in Jag's and BMW's. I will pay them a visit on Tuesday and see what they have to say.
Do you guys have any specifics on the fill process and the specific fluid that should be used?

Thanks!

 

Specs for fluid are in owner's manual or stickies on main page

 

See attached file.

 

I hope the engine parameters have been checked (via OBD II live data) as well as the battery since both are suspects and checks easily done.

 

UPDATE:

Took my car to a local independent shop that has a Jaguar Master Tech.
They found the transmission lines, pan, and sleeve are leaking. They feel that by fixing these leaks it should solve my slipping issue.
They stated that with the multiple leaks the transmission is likely not able to maintain the needed/required pressure to operate as it should.
Thoughts?

-Trevor

 

In order to check gearbox operation, having the correct fluid level is the first step.

 

I asked the specialty jag shop about checking the fluid and adding more if needed and then testing to see if it still slips, however they said with the leaks, pressure is likely the issue and will still slip even if the fluid is at the correct level.
Does this sound correct regarding trans pressure issues from the leaks?

 

My current plan is to bring my car back to the local shop that I had check/add the fluid to begin with. This is someone I have known for years and trust 100%, however he mainly works on American cars and is not very familiar with Jag's and ZF trans. Now that I have the ZF document about how to properly check the fluid level I'll follow up with him to see if that's how he checked the fluid in the first place. Also looking to have him verify the pan, sleeve, and trans lines are actually leaking as the other Jag shop stated. So I will know more regarding that stuff tomorrow and will report back.

 

It's a PITA service to do yourself with the car on floor jacks. There are also numerous threads on here about this procedure and the fluid(s) you can use. You don't have to use the expensive Jaguar branded stuff. But don't use just any old fluid that "might work". These transmissions are used in a lot of cars from that era. I also used an aftermarket pan/filter and gasket from Germany which was quite good. I found the sleeve troublesome to get in place but I was on my back with everything warm and a bit closer than I like.There are separate threads about fixing the trans cooler lines as well. They don't hold up very well. Some of us have done modifications to them rather than replace them and hope that the mods make them last longer. They also allow you to replace the hose portions near the cooler should they fail again.


I suggest you read all of the threads so can learn all the issues with doing these repairs.

You will be training your long term mechanic which is fine is he's one who can listen and accept advice. Like most tasks, the first time always takes substantially longer.

Good luck and stop driving the car until it's fixed.

 

Had the same problem years ago with the ZF and everyone, including the dealer tech said I needed a new transmission. A mechanic - savant at a small shop diagnosed the real problem as lack of power to the ZF due to some back pressure from the catalytic converter. New converter, problem solved.

 

 

PLOT TWIST:
Took my car back to my local mechanic that I know and trust. I verified with him that he checked and topped off the trans fluid correctly.
I also wanted him to verify everything was actually leaking that the other shop with the jag mechanic said(pan, sleeve, trans lines). The other shop quoted me $1,500 for the repair.
I have not noticed any leaks under my car on the driveway and my local mechanic never said anything about any big leaks when I have taken it in for an oil change.
My local guy gave it a good look over and said he does not see any leaks. He did say there is a small "film" on the trans lines, but not something he would call a leak.
So from here....IDK. Maybe I can find a transmission shop around me that has some experience with ZF. Frustrating

 

The transmission lines are known to weep at the junction where the metal pipe transitions into the rubber hose. It starts very slowly and that is when you may first notice the issue as a film accumulating on the lines. Sooner or later every one of these junction points begins to weep. Be sure to resolve your issue before you lose enough ATF to damage your ZF. My former 2005 S-Type was down nearly 1.5 quarts before I replaced both lines a few years ago. They had probably been weeping six months or more before I discovered the issue....

 

Have you educated yourself yet by reading all the threads?

Trust can be a wonderful thing as long as the person you're dealing with really knows what they're doing on this tranny. It's the same tranny for a lot of cars so he may know it well. But by you learning how it's supposed to be done you can intelligently query him and assess the situation better.

My leaks developed over time and you can find it inside of the belly pan. Usually once it's at that stage it's also spotting the driveway.

I had the good fortune to have both tranny and engine oil hoses leaking simultaneously.

Is there any record as to what type of fluid (brand & designation) was last put in the transmission?

 

Took my car to a trans shop. When I described the situation they said it sounds like a low fluid issue or valve body issue and would look it over at no charge.
They test drove the car and observed its behavior. They checked the fluid level, which they say is where it should be. No mention of any leaks.
They pulled two tans codes and multiple other codes, which I will post below. They suggested rebuilding the trans at a cost of $4900.
While my car was in the shop I did some reading and research about fluid level, fresh fluid, valve body and so on.
I asked about the valve body but they said after looking it over they don't believe the valve body is the issue. If I wanted they said they could drop the pan and replace the valve body gasket for $300.
I asked if that included new fluid and they said they would reuse the fluid that comes out. I questioned if draining the fluid and adding fresh fluid would be worthwhile, however they said old fluid would not cause the issue I'm having.

Codes they pulled:

P0735 - TRANS OBD II
Fifth gear ratio fault

P0730 - TRANS JAG
Gear ratio fault

P1582 - EMS JAG
“Flight recorder” data is stored if any one of five conditions occur:
1 Inertia switch activated 2 Throttle Limp Home mode 3 Engine starts and stumbles 4 Engine fail to start 5 Engine stall


P1410 - V8 SC EMS JAG
Air cleaner solenoid valve drive circuit malfunction


P0651 - TRANS OBD II
Pressure regulator and shift solenoid supply circuit malfunction


P0456 - EMS OBD II
EVAP system leak detected – very small (0.020 in.)



P0442 - EMS OBD II
EVAP system leak detected – small (0.040 in.)


P0171 - EMS OBD II
Bank 1 combustion too lean

P0112 - EMS OBD II
IAT Sensor circuit high voltage (low air temperature)


P0102 EMS OBD II
MAF Sensor circuit low voltage

P0101 EMS OBD II
MAF Sensor circuit range / performance

 

What is the age and condition of the battery? A failing or weak battery can cause many random DTCs to be stored.

With the ignition in the OFF position for at least ten minutes, check the voltage across the terminals. It should be a minimum of 12.6 volts, if not, the battery should be replaced before doing any further diagnosis or repairs.