Help Please: Rear end wandering after new tyres

[t.wak]

Hi Everyone

Now the obvious thing to say here is "Get new tyres you douche bag" but I have a gut feeling that it might be something else?

Last week I bought new tyres for the rear, Federal 255/40 R17. I chose these due to them being recommended by quite a few people as being good tyres for the money.

Ever since I picked it up, the car feels extremely unstable above 80km/h especially when overtaking, or going around bends.

The tyres have been on for a week and it's still just as bad.

I'm going to DECA this weekend for the driver training and want the car solved by then.

Could it be subframe bushings or something else back there? Or should I just buy new tyres?

Regards

Aden

[Torque]

Before you put them on, the car was alright ... you put on new tires, it's now unstable. I can't see anything else other than tires that would be doing it.

btw, What the hell is 'Federal'? Never heard of those tires.

[Ross]

I vote for the subframe bushungs allowing things to squirm around. Tires with a flexible sidewall will absorb some of this motion.

[BigKriss]

was the rear wandering about before the new tyreS?

[Barney Paull-Edwards]

Get Bruno`s Delrin inserts,if that solves it you know what to do next,and good luck!

[Omega]

I would check the obvious first before delving into suspension bushes. Something has changed. Does removing the change remove the problem?

Firstly check your tyre pressures. It's not unusual to find you have 45+ psi in them after a grease monkey has changed the tyres if they weren't paying attention (or gave a Damn).

If pressures are OK then I would swap the fronts wheels for the rears. Does the problem go away? If so, it's the tyres...

Something else to consider, is the new compound "harder"? My old hot-hatch hated Michelin tyres, far too hard and it skated all over the road. Swapped to Goodyear Eagles and all was sweet. However,, my money's on the tyre pressure.

[philbyil]

I would check your Pitman arms first then work up to the "major" suspension bushings/subframe bushings

[gale]

Ditto -- check the dogbones (pitman arms):

http://www.youtube.com/watch?v=_GEO6Ynwqmc

[BigKriss]

How did this work out for you. I just put the same tyres on the rear too.

[Tiger]

Change your front tire too (expletive)!... Seriously, I have a friend who wants to spend as little as possible... so he ordered the two new rear tires that I recommended to him. He then complains of rear end of being so out of control.

I said that is impossible for new tires to be so out of control. Check see if anything is worn out. So a month or two later, he bought second hand tires for front... didn't have the money... Coincidently, it was Federal tires too... and BAM... problem solved.

[Sam-Son]

whats the width of the rear wheels this may sounds simple and stupid but 255 is for a 9 or 10 inch wheel maybe you bought tires that are too wide for the wheels and theres a lot of sidewall flex

[t.wak]

I got the tyres balanced a couple of times before it began to get *slightly* better. About 2 weeks later one of the tyres sidewalls failed so I said stuff it and bought 4 brand new ContiSport Contact 3s... Now she handles like she's on rails again.

[Sam-Son]

justgot some pirelli p6's on mine and theyre really good just thought id mention it

[bubba966]

I got the tyres balanced a couple of times before it began to get *slightly* better. About 2 weeks later one of the tyres sidewalls failed so I said stuff it and bought 4 brand new ContiSport Contact 3s... Now she handles like she's on rails again.

Don't know about your neck of the woods, but around here Federal is pretty low end. So I'm not terribly surprised they sucked on your car. E34's don't really do with with so-so tires. Gotta put better tires on them than most cars to keep them driving properly. Which is why I've had either Pilot Sport PS2's or Pilot Sport A/S's on mine.

[t.wak]

Yeah well they got recommended as being good tyres for the money so I thought they were worth a shot. Perhaps I got a dodgy batch or something but on this car... Never again!

[BigKriss]

the minimum wheel width for the 255 tyres is 7.5" quoted by the manufacturer.


whats the width of the rear wheels this may sounds simple and stupid but 255 is for a 9 or 10 inch wheel maybe you bought tires that are too wide for the wheels and theres a lot of sidewall flex

[Tiger]

Pirelli P6 is really really old technology... like 1980's when it first came out.

[Tiger]

Whoa... I didn't know this thread is over 6 months old... Like I said... changing all 4 tires makes all the difference. Worn front tires makes new rear tires seem out of control.

[t.wak]

Could've also been the fact that the Federals were an aggressive directional tyres where my fronts we ContiSport Contact 2s? Who knows, all I know is that I'm happy 6 months on with the new Contis. :)