2002 XJ8 "humming" noise at 52-55mph
 

We just purchased a beautiful dark blue XJ8 with 60,000 miles on the clock. After about a week, the muffler began to sound like a tank, and a BIG tank at that. We brought it back to the dealer (who has been treating us royally) and they installed a brand new muffler.

There is one other "issue" we are having with the car. On the highway at speeds between 52-55mph we can hear what I would describe as a "humming" noise - it's annoying and only happens at that speed and appears to be coming from the front of the car (engine).

We took the car back to the dealer and they told us it was the tires and they put a brand new set of tires on the car! Unfortunately, on the drive home, the same old noise was still there, only this time the steering wheel is vibrating at the 52-55mph speed.

We are bringing the car back to the dealer tonight and taking the mechanic on a test drive with us on the open highway so we can show him what we are talking about, but in the meantime, has anyone experienced this before or have an idea what it might be?

Thank you!

I'm sure this could be any number of things, but I did have a problem with "Humming" when I had a temporary tire on my car. It was a Pirelli PZero 255/40 ZR 18 Asimmetric Non-Directional.

It sounded to me like a wheel bearing that had gone out. But when I moved the tire to the rear, the sound followed it. I've since tried it on the other side, and again the sound followed.

Again, yours could be a different issue, but I can confirm that some tires will make loud humming noises.

The Vibrating Steering Wheel I would assume is improperly balanced tires, or out of round tires since it just happened with the new tires. I'm REALLY picky about noises and balancing, so I completely understand. But, beware, your dealership has gone well out of their way to try and fix it, and may throw up their hands soon... :o

Thank you for your feedback. "Humming tires" makes sense, but the noise we encounter only happens during acceleration (not when coasting or when cruise control is on) at 52-55 mph.

We did finally take the car out for a ride with the dealership's master mechanic. He quickly identified the vibrating steering wheel as a tire balance/alignment problem, and he will be taking care of that for us. He told us that he had "zeroed" them out (whatever that means) but that he would take the car to another dealership in Charleston who has some kind of more advanced machine/computer/whatever and that should make things right.

The humming noise he is not sure of. We are bringing the car back down there today so they can work on it next week.

Yes, the dealership has REALLY done out of their way for us on this car. And we appreciate it.

Thanks again for your post.

2001 XJ8VDP "humming" noise at 52-55mph
 

Hi, I have exactly the same noise you are talking about. I have only owned this XJ8 since February and don't drive very much on the highway but I noticed this noise at those speeds and it only occurs when the engine is pulling the car, be it acceleration or crusing speed. When you close the throttle, the noise disappears. I was a mechanic in my younger years and in any old common domestic car, I would say this was a bad pinion bearing(s) but with this Jag, I'm not very familiar. My car has 47K on it and otherwise runs and drives beautifully. Any suggestions out there from you experienced Jag guys would be appreciated. Thanks.
Spillwaybob

Have all your universal joints checked first driveshaft and both halfshaft assembly. They need to be lubricated and are often overlooked.

Buzzing Noise
 

I had a buzzing noise in the front end of my 2000 VDP and it sounded like it was coming from the dash. It ended up being the right hand side defrost vent up near the windshield (long skinny black vent). I pushed it back down and the noise went away. Hope it's that simple!! Congrats on your new car!

Hi Gus, thanks for that good advice. I checked in my Jaguar maintenance schedule and nowhere does it say anything about lubricating the drive shaft and half-shaft joints. I'm sure glad to find out about the zerk fittings and have already lubed the half-shaft joints. I have to get the car up higher so I can take care of the drive shaft oness. U R right, it doesn't look like they have been lubed in a long time.
When I'm finished, I'll let you know if I fixed the humming noise. Thanks again.
Spillwaybob

Bob, would be interesting to know the outcome as I have exactly the same noise at exactly the same speeds and under exactly the same conditions. My VdP has 68k miles.

Cheers,

Steve.

The other thing moving at the front end is, of course, the fan, and fans can hum as we all know !

I have the exact same noise at those speeds, I just ASSUMED though it was the engine and that jaguars RPM didn't agree with those speeds. The noise goes away if the speed isn't in the range 50-53mph so thats what I assumed.

Looks like more people have this same noise than I thought. It's definitely not an engine noise as it only occurs in 5th gear. It's not cooling fans as their rpm's are constant and you can't hear them at highway speeds. I'm still thinking rear axle ring gear/pinion or pinion bearing(s). Also could be transmission although I haven't listened for the noise with the trans. in 4th gear. Another question, is this problem peculiar only to XJ8's?
Spillwaybob

Hi Gus,
I founs 4 zerk fittings on the half-shafts but can't find any on the two piece driveshaft.....the only U-joint on my driveshaft is in the middle just above the center driveshaft bearing and I rotated it 360 and can't find any zerks. At the front of the front shaft and at the rear of the rear shaft are large fllanges but no U joints. Can you advise me on this and could mine possibly be different than yours? Thanks again for your help.
Bob

It is called a flexible jurid coupling. You should check the integrity of it. I understand that they dry out and can crack causing it to become unbalanced when spinning.

https://www.jaguarforums.com/forum/a...8&d=1270765530

One not:
The speed range mentioned is the transmission torque converter lockup speed.

I had two vibration situations one was the universal joint drivers side and the other was the failure of my A&B drum in the transmission. I hesitate bringing up the transmission because of my limited knowledge with it.

Gus, thanks for posting a break down of the propeller shaft. I did not inspect the jurid flexible couplings for cracks...will have to get the car jacked up again to do that. I have only driven it briefly since I lubed the half shaft U joints and the noise was not present. I hesitate to say the problem is fixed without more extensive road testing but I am optomistic. Will let you know and thanks again for yours and everyone elses help.
Bob

Sounds Good! On the road again!

Gus, good news and bad news. Bad news, the noise is still there.....good news, I found out how to make it come and go. Without changing your speed fraom 52mph, shift the transmission from regular mode to "S" mode. The noise is there in regular mode and disappears in S mode. The rpm's don't change (car stays in 5th) so what is making the noise? This throws a whole new light on the problem. I usually drive the car in S mode so that's why I didn't hear the noise all the time. Any ideas?
Bob

Bob,

Hard for me to say what is going on. The transmission is an area that I am not versed in. I wish we had a transmission person that could help. I know that when mine had the humming it would take place around 45 – 50mph. Not long after that I had the transmission failure. I think it is listed under the xk8 FAQ A&B drum. You can also look on my page http://www.gusglikas.com/AutoRepairTransZF5HP24.htm and what info I do have. Sorry I do not have additional information and I was hoping that it was the u- joint and not the trans.

I must say that I do not think you have the same trans that is in my xk8 so I would be guessing on your problem.

Does the torque converter unlock in S mode at that speed? You can tell by driving until you hear the 'rumble' and slightly modulate the throttle, while watching the tachometer - if the tach moves with your throttle motion the converter is unlocked; if the tach only changes with road speed it is locked. Compare this between S mode and regular mode - I'll bet the converter is locked in regular (making the noise) and unlocked in S (not making the noise).