70mph steering wheel judder = leaky rack?

[TimC]

Hi all

Not too long after buying bongo last year noticed that at motorway speeds has developed vibration through the steering wheel.

Assumed lost wheel balancing weights or whatever.

Anyway, have had tyres changed and wheels balanced (twice) and still no different. led me to think it may be a buckled alloy

Reading the FAQ's suggests it may be related to a leaky steering rack - I do have a leaky rack (!) and have used some power steering leak stopper stuff as a temp fix.

How does a leaky rack = 70mph wobble?

If likely to be cause - how difficult to replace/remove and service the rack?

Cheers

Confused

Tim

[dave_aber]

Check that you don't need spigot rings.

I was convinced that I didn't, and that the slight / intermittent wobble I had at 70-75 was down to a wheel issue.

Then I measured the wheel centre hole and the hub - they were different.

A set of spigot rings from eBay at about £5 sorted the issue out.

You do need to measure accurately though - down to 0.1mm

[wonkanoby]

What about inner bore of alloys,cannot see rack like that my self

[daveblueozzie]

Also check you have the right wheel nuts for your alloys, i had wheel wobble and had the wheels balanced three times with no luck, I eventually took it to wheelquick and they said you've got the wrong nuts for the wheels, they sorted a set for me and cured the problem.

[Simon Jones]

Are they genuine Mazda wheels or aftermarket universal fit with more than 5 mounting holes? If the latter, then it sounds like spigot rings may be the answer.

Have you tried swapping front and rear wheels over to see if the problem gets better or worse? Personally, I've not heard of a steering rack causing wheel wobble, but i guess it's not impossible.

My 15" Mazda wheels are pretty straight, but the van tyres are less so such that when they were balanced they were using about 90 grams of weights to even them out. They still wobble at about 60, but I've got used to it being a 'characteristic' of the vehicle.

[Northern Bongolow]

a faulty rack may give you problems, if the one side or both is leaking,the hub will try to tow in then out etc as it compresses the air thats present instead of fluid. when it wobbles try altering the steering slightly so it may top up the internals of the rack, (hard to do at 70mph ).

if it is the rack at fault its only an hour of a job to do, plus tracking after.

[hijimhere]

I had a distinct wobble under braking especially from speed -- not yet taken mine above 65/70 -- I changed the pads and noticed the discs were in good nick with no ridge formed. The discs were not blued by excessive heat on the side which was found to be sticking. The odd thing was that the lightest of pressure on the brake pedal would bring the symptoms on. I was expecting the problem to still be there as I had concluded that the ns disc at least had run out. Surprise, new pads fitted problem cured.

[TimC]

Cheers all

I have no idea about the wheels - they are 17" so probably not standard.

Will check through various things with the wheels et al. All makes sense

The rack does need overhauling anyway so . I'll see if I can find a s/h one and can refurb it so I can do a straight swap