Boost Issue And Braking, Steering Shudder

[Benji_vs]

If no one has mentioned it, maybe change your spark plugs, it seemed to fix a similar problem I had.

[geekatrons]

I will give you an update- once I get to the bottom of this. I think I will get plugs etc and eliminate some of the things I should change as preventative maintenance anyway.

Cheers all.

[geekatrons]

Hello All

Quick update re the shudder. So I have just completed the front and rear disk rotors (DBA Slotted) and bendix brakes. This made a slight difference to the shudder (Not so Violent.) Then I went to tyre place and got a wheel balance done- I know the guys pretty well so had a really good look at the rim on the balancer and noticed a bad wobble in one of the front wheels. (Bent rim) As my rear tyres are really worn I am due to get new tyres and was going to swap the fronts to the back.

Should I just buy a new rim or try it on the back and see how I go. I think that this bent rim may be the issue for my shudder as it looks very buckled even at around 40kmh.

Another point to note the car shudders more than ever since balance so I am thinking that removing the weights may have been kinda hiding the bent rim a little?

Anyone have experience with bent rims- on the back will it shudder through the car?

[geekatrons]

Hey All

I have a BA XR6T. Have had it for a few months and had the normal shudder etc that is pretty common. Anyway I have gone and updated the brakes to slotted DBA front and back and bendix front and rear. Got front balanced- no real issue in fact was a little worse- turned out one bent rim. Just got 2 new tires so swapped wheels from front to back and still has a wobble in through the steering wheel and a shudder under braking. What should I do next, I know I have 2 slightly buckled wheels but I don't think this is the real issue. could it be that the steering fluids need flushed and replaced? could this be a wheel bearing, bushes issue? It doesn't seem to get better or worse with speed. In cold weather it appears to be better than any other time?

Your advise is appreciated!!

[MX Dave]

Shudder under braking is normally buggered rotors.

My bet is they were installed incorrectly or the more likely option your wheel nuts have been over tightened.

[Shyfrd]

Was the hub given a clean before the rotors were put on? Have heard of some of that stuff staying behind on some cars and making the rotors obviously not true flush and "wobble free" lol

[geekatrons]

I am taking the car back to my mechanic this friday. The rotors should be 100% as they have only been on for about a week. What I will be doing is getting the fronts removed/ cleaned and then re set. I will get the abs sensors cleaned, get the 2 most true wheels on the front, bleed the brakes, new fluids and then see how I go.

I hate it.

On a side note I am thinking of getting new wheels to ensure that I have no questions around them, but will see. would rather fork out for fuel than wheels though.

[MiKa]

All the above could be the cause, but rooted front bushes, esp cause yours is a BA, if they haven't been changed they could be making a slight wobble worse. I had pretty bad shudder, changes my front upper and lower bushes to super pro, and it fixed 80% of the shudder, the rest I have put down to the rotors being rooted as a result and ill be changing them soon..

[geekatrons]

The car feels really different now since getting the fronts balanced. I feel vibration more, I know one wheel was buckled but maybe it is just the wheel was balanced better to counteract the bent rim. Also the car on idle seems to make the steering wheel shudder a little? I know weird.

Will see how I go.

[discostig]

I was similar to Mika. Even having DBA4000 slotteds on the fronts, I had bad shudder under brakes, but was kind of intermittent as well, sometimes far worse than others, but almost always there in some form.

New bushes up front fixed it 80%, then I changed pads to remsas which seemed to flatten the warped rotors like an on car brake lathe hahaha...that's my theory anyway as the shudder is now gone. Stopping in confidence once again.