au irs rear wheels feel hot after a little highway or freeway driving

[mif73]

Hi.
Just took the au s1 fairlane with irs for a 50km trip at speeds between 80 and 100kmh.

Rear wheels feel much hotter than fronts. Not to the stage that you cant hold your hand there, it that the fronts feel just a tad warm and backs feel hot by comparison.

The rear bearings were recently replaced with quality jap bearings and torqued to 325Nm.
Hand brake was set loose. Wheels are 17" au xr style.
Any ideas besides rear calipers seized?

Any one with irs notice this too?

[Bushbasher]

How old are the tyres and are they worn unevenly? Check the inside shoulder of the tyres for scrubbing out. That'll indicate that the rear bushes are on the way out and the wheels aren't tracking straight. With both wheels having toe out they are effectively being dragged sideways up the road which would heat up the tyre and hense the wheel eventually.

[mif73]

All the outer sphericals were replaced at the time of replacing bearings.
Inner bushes seem to be ok, although i notice some slight sideways skipping if driving over asphalt joins etc on a slight bend etc. I thought that it could be due to no rear sway bar fitted on non xr au s1 irs.

My pass side bearing was badly worn and damaged the hub and possibly accelerated the wear on the pass side spherical joints etc which have all been replaced with new hub.

.tyres are cool in comparison to centre of wheels.

Car has 130,000 km on clock and no tyre feathering.


Cheers
Andrew

[Bushbasher]

Hmmm, strange that there's no sway bar on S1. My S2 has a sway bar but then it's also a Sportsman with XR suspension. That little bum wiggle on bumps is a sign of soft bush movement. My #1 Sportsman started doing the same thing and it eventually killed the whole rear end. I decided to go buy another one rather than rebuild the entire suspension front and rear but even the replacement car has a hint of the wiggle so I'll be changing out the lower control arm bushes as soon as I can afford to.

As for your wheels being hotter than the tyres, that's a strange one and I don't have anything helpful, sorry.

[mif73]

I might jack the wheels just off the ground again to check for brake binding again and check irs inner bushes with a crow bar for the unsettled rear end problem anyhow.

If the inner bushes need doing i can prob change the lowers on the car with my rattle gun and high tensile thread like i used to get the outer sphericals replaced.
The uppers would be tough to do without dropping the sub frame - ouch!

Getting a wheel alignment soon after i convert front end to s2 brakes with new components.

Mine has a Tickford plaque in the engine bay and states it has the 17" wheel option but no mention of suspension.
It has red coils in it and sits at about xr height. I think they could be pedders springs fitted later on by the previous owner.

Cheers,
Andrew.

[mik]

i think its the norm for the rear end/wheels to have a bit more heat than the fronts on a highway run isnt it? the rear wheels are being driven to push the car along, driveline friction and tyre friction from the roadway, front wheels are basically castors once cruising.
i know the drive wheels/axle in a truck get nice and hot after a run.

[FTe342]

Plenty of people have had the rear bearings go loose after having them replaced. I would jack it up and check for any movement.

New bearings doesn't always fix the problem. Some have had to replace the the hub assembly to get a permanent fix. Its something like the seat is machined or worn too deep from memory and no amount of new bearings will fix it. This was not entirely uncommon in some cars from new and a new hub assembly the only fix

[mif73]

Originally Posted by FTe342

Plenty of people have had the rear bearings go loose after having them replaced. I would jack it up and check for any movement.

New bearings doesn't always fix the problem. Some have had to replace the the hub assembly to get a permanent fix. Its something like the seat is machined or worn too deep from memory and no amount of new bearings will fix it. This was not entirely uncommon in some cars from new and a new hub assembly the only fix

Yep the pass side hub was scored and replaced with a new one along with new bearings . The drivers side was not loose or noisy at all but both sides where replaced together.
I checked torque again a few days ago and it is still tight at 325Nm also the mark i put on the new nuts did not move.

The issue of hub damage is because when the tapered races of the bearings wear out, they go loose on the hub and rub instead of being a press fit.
Its how they made the bearing id smaller.
I dont like cartridge bearings for the fact that the opposing races are too close to each other for the load carrying task and it seems ford underspecced the bearing size in this application.

.

[Mitch_]

if you're that worried about it you could possibly run some window wiper squirters pointing towards the rear tyres to cool them down

[mif73]

Originally Posted by Mitch_

if you're that worried about it you could possibly run some window wiper squirters pointing towards the rear tyres to cool them down

Yeah yeah funny hehe. Its actually the wheels that are hot tho.

[Mr Hardware]

dragging brakes/handbrake perhaps?

[mif73]

Originally Posted by Mr Hardware

dragging brakes/handbrake perhaps?

Ta mate.
Just checked rears jacked from lower control arm,
wheels just 10mm from the ground.
No binding even when i pump then release the brakes with engine on or off.

Handbrake has been free and backed off since bearings were changed.

Will have to check centre of wheels with IR thermometer next time i cruise.

Starting to think it might be normal for this irs setup possibly adding to the early failure of these irs bearings.

Will post temps front back and left right soon so others can compare perhaps?