I've noticed recently two noises that my car makes that it didn't make a few weeks ago. One, on hard acceleration it seems that there is a "whooping" sound made by the transmission on one of the shifts. I notice no problem with the car itself, just this bizarre whoop. What is this?
Second, any time I touch the brake pedal or release it I hear what almost sounds like a musical tone, a click of sorts sounding like it is coming from the lower left side of the driver side dash. Do relays make noises sometimes?
Are these noises anything I should concern myself about?

 

The whoop is pretty well known and apparently solved by replacing the fluid with one that has some additive. Don't know the details offhand but if you google Jaguar and "whoop" or "bark" you will find the details.

Can't help with the musical tone unless a mechanic left a xylophone back there.

Doug

 

dealer confirmed an additive was used to replace 1 liter of the original transmission fluid but that it is no longer available. Any idea where I can find this additive? I understand that the noise is just a cosmetic issue but still want to pursue it.

 

Could it be coming from the Brake Pedal Switch (item 14)?



(click on the image to enlarge it )

Graham

 

Thanks to both of you. What does the brake switch do?

 

Brings on the brake lights, deactivates cruise control and also the gear lever selector solenoid.

 

With the ZF ATF additive apparently no longer available, your best bet for silencing the ZF 6HP26 "bark" is to do an ATF drain-and-fill. Since the transmission pan has the filter built into it, you may want to spring for a new one as well. And if you do that, be sure to get a new electrical connector sleeve since the original sleeves tend to leak ATF after a few years pass. The only way to do that is to drop the pan....

There's a company in California that sells this ZF fluid change kit for what most of us deem to now be a very reasonable price. Go to The CTSC - ZF Parts and check it out. If you have questions, e-mail them. Klaus (the owner) will respond....

Plenty of threads about this procedure here on the forum. Just search "transmission fluid change", then sit back and do some heavy reading....

 

The whoop is the E Clutch in the transmission sticking due to incorrect friction modifier conditions. Replacing the tranny fluid and filter pan is the only resonable fix. I paid about $600 for this service including buying the parts from CTSC. I keep hearing that this won't hurt anything, but I think this is only positive thinking, a sticking tranny clutch is not going to be good in the long run as it works the bearings and cyclical gearset pretty hard. The sound is pretty loud to hear it through the case above all the other sounds during this acceleration. I fixed mine immediately after I heard it.