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View Full Version : Broken top mount (again) and also a tranmission question.



TDiBoraSam
09-08-2013, 08:24 AM
The following refers to a 57 reg Jetta TDI - BXE Engine.

Could anyone out there tell me if the following are symptoms of a broken top mount and/or bearing failure;

1. Car won't drive in a straight line - often lurching around and very susceptible to winds or drafts from other vehicles. Particularly unstable at motorway speeds, needing constant steering correction.
2. 'Jarring' feel to the suspension.
3. Occasional crunching/rumbling noise when turning at low speed - coming from nearside front.
4. Very occasional sticky steering.

Add to that, brakes that have started shuddering this week, with pulses felt through the pedal and steering wheel. Under heavy braking the car pulls to the left, which is the side the noises are coming from. New discs and pads fitted 6 weeks ago.

The car has had top mounts replaced just over a year ago along with new shocks - the nearside mount was in bits.

I'm just wondering if lots of poor roads and speed humps in my area, combined with Bilstein B4's are stressing the mounts to failure? Are there any uprated/stronger mounts available from VW, such as off a more powerful model?

For info, the car has been inspected twice, with no readily visbile problems detected. It also passed an MOT 2 weeks ago.

My other question relates to transmission;

When driving at steady speeds, such as 20mph in 2nd, or 30 mph in 3rd, the car randomly shunts. I can only explain this as a feeling of momentary loss of drive. It's as if the engine can't decide whether to apply drive or not (if that makes sense). Sometimes it is subtle, and other times it is quite violent. No abnormal noises accompany this. Nobody has been able to diagnose it. I've had a new clutch and DMF about a month ago, and the shunting has remained the same as it was with previous clutch.

The car is also quite jerky when going on and off the accelerator when in gear, and kind of feels like there's play in a mount, but again, the car has been inspected and all mounts appear to be fine. Sometimes when putting the car in 1st gear there is resistance and a slight thud. If I take it out of 1st again, and re-select, without releasing the clutch, it goes into gear smoothly.

I'm wondering if replacing the dogbone/sub-frame mount might help?

As always, any ideas/advice appreciated.

Doctle Odd
09-08-2013, 08:37 AM
Is the gearbox mount broken? Boy wonder (son) had a similar problem with his Bora the bolts holding the top mount to the box had snapped and the engine/box were at a mad angle

TDiBoraSam
09-08-2013, 12:28 PM
I don't think so. The car has been inspected, and nothing wrong could be seen.

I have been trying to get to the bottom of exactly how many mounts a BXE engine has including subframe and gearbox - even VW couldn't give me a proper answer!

TDiBoraSam
12-08-2013, 12:46 PM
Further update on this problem...

I started the car yesterday morning, and when the engine fired there was a very loud, very heavy bang and the gearstick shook violently backwards and forwards.

This has happened once before, last year, when I had an SMF fitted, so the fact that it's happened again having gone back to DMF rules out any kind of clutch problems.

I'm certain a mount is at fault, but nobody seems able to diagnose it!