[Fot] TR4 High speed driveline vibration

[Duncan Charlton]

Jim,

How are your motor and trans mounts?  If they allow the engine/gearbox combo to shift out of line when under high torque, the u-joints could move out of proper alignment, but then when power is reduced, things would shift back into position.  If you put the car on jackstands and run it to this rpm in top gear (might not be a bad idea to remove the drive wheels and tires if you’re sure they’re balanced) there won’t be much load on the engine, so if the vibration is due to deformation of the mounts, the vibration should not appear.

Duncan


> On Jun 15, 2015, at 10:55 AM, toodamnfunky at comcast.net wrote:
> 
> FoT,
> I have a driveline vibration that doesn't start up until I get to about 95- 100 MPH. I figured I would start with the driveshaft
> before looking into the diff or OD/trans. I have an IRS car with Richard Good CV axles and hubs so it's very un likely its that but
> I will inspect them. I'm wondering if anybody has any advice on high speed vibration diagnosis or detection.
> What I'm wondering is even if it is the driveshaft how would I know with it sitting on my bench.
> Any help would, as always be greatly appreciated.
> Jim g
> _______________________________________________
> fot at autox.team.net
> 
> http://www.fot-racing.com
> 
> Donate: http://www.team.net/donate.html
> Archive: http://www.team.net/archive
> Forums: http://www.team.net/forums
> Unsubscribe/Manage: http://autox.team.net/mailman/options/fot/duncan.charlton54@gmail.com
> 
> 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://autox.team.net/pipermail/fot/attachments/20150615/09ecd12c/attachment-0001.htm>