low engine speed vibration?

[dan_b]

Been meaning to post this for a while now...

Since fitting my rear diff mount Powerflex bush, which cured the off-throttle transmission shunt I was getting, I've noticed something else perculiar instead.

If you're pootling around in traffic, at around 1300RPM, usually in 2nd and 3rd gears, if I accellerate with anything more than feather throttle through that rev band, I get a quite noticable vibration through the chassis, which will sometimes skip the CD player mounted in the boot.

Is this something to do with the Powerflex bush simply being more rigid, and isn't dampening the transmission vibrations when the engine is at load, or have I messed up the installation somehow! The car drives fine otherwise, performance and handling are as before.

It's a wierd one. Anyone else with the Powerflex diff mount have this? What have I done?!

Dan

[scouser_75]

Dan, just a rough guess, from a total car thicko, but maybe you need to re-do your tracking and alignment.

I know that when I got my bushes and stuff done I too was getting vibrations when driving. But once I got the tracking and alignment done the vibrations were gone.

The only weird thing about your situation is that you only get the vibes at low speeds! Hmmmmm?

[S2 Ant]

could still be tracking or balancing etc, judder from poorly balanced wheels will only affect certain speeds, so i wouldnt rule allignment etc out before getting it checked and the best bit about getting that done is checking is FREE

[Graham]

I have just ordered my powerflex diff bush as i have a low vibration/humming from the back end at about 70-80mph. When i floor it it almost goes away, when i back off it goes away, when i cruise it is constantly there. It could be the propshaft to differential input bearing as it does get alot of stick coping with all the mis-alignments of a car such as these, especially if the diff mount has gone. While i am there i have yet to fit the rear powerflex wishbone bushes, so i may aswell do them.

[martinjs]

Dan, when were your w/bone bushes changed last, maybe not the cause of your problem though, i'd recommend fitting powerflex ones all round then get all the alignment done, ive just done all this along with new b/joints and track rods and it has transformed the handling, over bumpy back roads it feels planted to the road, just the RS2 front arb needed now.

martin

[dan_b]

Well I know my front right strut mount has pretty much died (groaning when turning steering at parking speed, worse if on a camber), my steering rack still leaks (have to top it up every 2 weeks), both ARBS are showing signs of corrosion and could do with replacing, and I don't see any evidence of when the last time the wishbone bushes were changed, or the tracking done, and apparently all 4 of my Cup replica alloys are wobbly as when I changed the tyres recently they had to put mad balancing weights on, and the car doesn't quite pull up straight under heavy braking, and it's tramlining more than it used to on rutted M-way lanes: BUT, this vibration phenomenon has only reared its head with this Powerflex doo-dad.

Anyone know where I can get a proper 4-wheel alignment tracking done in Richmond/West London/Surrey?

Anyone want to volunteer to completely overhaul my suspension

[martinjs]

think 'the autopool' in iver are very good

martin

[dan_b]

My wife's not going to be impressed if I start shelling out wads of cash on the red beastie again

[Beetie]

Never mind just dont tell her!

My wife's not going to be impressed if I start shelling out wads of cash on the red beastie again

[scouser_75]

Dan,

I'll second The Autopool.

I'll also second not telling the Missus

Discalimer: In no way have I guided Dan into hiding costs from the Missus. If Dan gets his rear whooped by the Missus for not telling her about the costs, I can not take any responsibilty.

[Beetie]

Dan,

I'll second The Autopool.

I'll also second not telling the Missus

Discalimer: In no way have I guided Dan into hiding costs from the Missus. If Dan gets his rear whooped by the Missus for not telling her about the costs, I can not take any responsibilty.

Good point, me too

[scouser_75]

Beetie, you can't back track now when you were the one who first advised Dan not to tell her!

[dan_b]

Suddenly, joint bank accounts don't seem such a good idea eh?!