| Porsche Enthusiasts Club Forum https://forums.tipec.net/ |
|
| 944 transmission rumble https://forums.tipec.net/viewtopic.php?f=25&t=21716 |
Page 1 of 2 |
| Author: | NeilF355 [ Wed Jul 27, 2016 2:13 pm ] |
| Post subject: | 944 transmission rumble |
Hi all I have a problem with a transmission rumble on my 1991 944 S2. The noise starts at about 30 mph and gets steadily louder as my speed increases. It's present in all the higher gears and when the transmission is loaded and unloaded. I've tried the usual trick of changing the transmission fluid but to no avail. I'm not sure if it's coming from the transaxle or the torque tube. It's not the sort of whine that indicates the diff is worn, more a sort of low frequency rumble. Anyone had a similar problem or any thoughts on what it could be? Neil |
|
| Author: | tr7v8 [ Wed Jul 27, 2016 2:33 pm ] |
| Post subject: | Re: 944 transmission rumble |
Possibly a torque tube bearing. First I'd be dropping the driveshafts & checking the CV joints as well. |
|
| Author: | pilch [ Wed Jul 27, 2016 5:04 pm ] |
| Post subject: | Re: 944 transmission rumble |
Sure its not a rear wheel bearing? I thought my box was on the way out but it was just an incredibly noisy wheel bearing with the same symptoms you describe. |
|
| Author: | blackadder30 [ Wed Jul 27, 2016 11:31 pm ] |
| Post subject: | Re: 944 transmission rumble |
If it's road speed related, I'd go for something between diff and wheel bearing. If it's engine speed related, torque tube is a possible.... Perhaps try getting up to speed, dip the clutch, put into neutral and see what noises are present with different parts of the drive train loaded or unloaded... Weaving from side to side can help tell you if it's a wheel bearing. Good luck 
|
|
| Author: | NeilF355 [ Thu Jul 28, 2016 10:28 am ] |
| Post subject: | Re: 944 transmission rumble |
Thanks for the replies guys. I've had the rear on axel stands and I can't detect any play in the rear wheels to indicate bearing problems. The noise does seem to be road speed related, I don't seem to get any noise in first gear, but when it's up to speed and in neutral I still get the noise. |
|
| Author: | pilch [ Thu Jul 28, 2016 6:33 pm ] |
| Post subject: | Re: 944 transmission rumble |
NeilF355 wrote: Thanks for the replies guys. I've had the rear on axel stands and I can't detect any play in the rear wheels to indicate bearing problems. The noise does seem to be road speed related, I don't seem to get any noise in first gear, but when it's up to speed and in neutral I still get the noise. Exactly as I was, no play in the bearing at all. Same noise symptoms. I'll still have my money on a rear wheel bearing 
|
|
| Author: | briggy [ Thu Jul 28, 2016 7:27 pm ] |
| Post subject: | Re: 944 transmission rumble |
Please don't read this as patronising in anyway as I'm genuinely trying to help, but have you ever heard a worn wheel bearing? The noise you describe fits exactly what I've heard on 2 previous cars, with the solution being to replace the wheel bearing in each case. On the first occasion, I was worried it was something terminal, but on the second occasion, I knew what it was straight away. Cheers, Bryan |
|
| Author: | NeilF355 [ Fri Jul 29, 2016 10:38 am ] |
| Post subject: | Re: 944 transmission rumble |
briggy wrote: Please don't read this as patronising in anyway as I'm genuinely trying to help, but have you ever heard a worn wheel bearing? The noise you describe fits exactly what I've heard on 2 previous cars, with the solution being to replace the wheel bearing in each case. On the first occasion, I was worried it was something terminal, but on the second occasion, I knew what it was straight away. Cheers, Bryan Hi Bryan No offence taken at all, I appreciate your help. As well as an absence of play I couldn't hear any noise when I rotated the rear wheels with the car on axel stands. Did you decide it was a wheel bearing purely from the noise the car made on the road or could you hear anything with the rear wheels off the ground and the wheels rotated by hand? I am almost tempted to change the wheel bearings anyway as a first step, as it won't cost as much as a refurbished torque tube, diff or gearbox. Cheers Neil |
|
| Author: | NeilF355 [ Fri Jul 29, 2016 10:42 am ] |
| Post subject: | Re: 944 transmission rumble |
tr7v8 wrote: Possibly a torque tube bearing. First I'd be dropping the driveshafts & checking the CV joints as well. Thanks for the info Jim, I've ordered the 12 point spline drive I need to disconnect the driveshafts so that I can check the CV joints. Cheers Neil |
|
| Author: | tr7v8 [ Fri Jul 29, 2016 2:20 pm ] |
| Post subject: | Re: 944 transmission rumble |
NeilF355 wrote: tr7v8 wrote: Possibly a torque tube bearing. First I'd be dropping the driveshafts & checking the CV joints as well. Thanks for the info Jim, I've ordered the 12 point spline drive I need to disconnect the driveshafts so that I can check the CV joints. Cheers Neil Worth checking the CV joints & gaitors at the same time. Also repacking with clean grease. Filthy 'orrible job but worth doing. Note that officially the bolts are stretch bolts & shouldn't be reused. Either replace or use some Loctite. |
|
| Author: | pilch [ Fri Jul 29, 2016 9:30 pm ] |
| Post subject: | Re: 944 transmission rumble |
NeilF355 wrote: tr7v8 wrote: Possibly a torque tube bearing. First I'd be dropping the driveshafts & checking the CV joints as well. Thanks for the info Jim, I've ordered the 12 point spline drive I need to disconnect the driveshafts so that I can check the CV joints. Cheers Neil If those bolts have not been touched for 25+ years then be prepared to cut them all off! The spline heads on mine were rusted and there was nothing left for the tool to grip on 
|
|
| Author: | blackadder30 [ Sat Jul 30, 2016 10:22 am ] |
| Post subject: | Re: 944 transmission rumble |
I bought these bolts for the 968, I believe they're the same on the 944 -£1 each plus postage.... https://www.ebay.co.uk/itm/181856392919 Hammer the triple square bit into the bolt head before you try to undo them that will give you best purchase... Good luck
|
|
| Author: | NeilF355 [ Mon Sep 19, 2016 9:47 am ] |
| Post subject: | Re: 944 transmission rumble |
After problems with my Mondeo daily driver I've finally managed to get around to looking for the cause of this rumble. Removed the drive shafts and checked the CV joints, all OK. Next took off the caliper and disc and so that only the hub was left on. When I turned the hub by hand it made a terrible racket and I could actually feel it grating as it turned. Definitely the wheel bearing so you were spot on pilch and briggy. Replaced the bearings on both rear wheels and now they are smooth and silent, job done. Many thanks for all your helpful replies guys. Neil |
|
| Author: | pilch [ Mon Sep 19, 2016 2:25 pm ] |
| Post subject: | Re: 944 transmission rumble |
Excellent stuff, no doubt the cabin is a much more pleasurable place to be in now
|
|
| Author: | briggy [ Mon Sep 19, 2016 4:04 pm ] |
| Post subject: | Re: 944 transmission rumble |
Great stuff. Glad it was something relatively simple. Sounds like you did the work yourself, which makes it all the more satisfying. |
|
| Page 1 of 2 | All times are UTC |
| Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group http://www.phpbb.com/ |
|