Diagnose Front End Problems Using Tire Tread Temperature?

[Dibbons]

I know there is a way to use tread temperatures across the width of the tire to diagnose stuff (NASCAR does it) but a quick internet search showed nothing. I noticed after a 15 minute drive the outside tread of the front tires was warm to the touch and the inside tread was cool in comparison. This is the '72 Satellite Sebring Plus 318/auto.

 

[moparedtn]

Is there a noticeable wear pattern difference?
Does the car steer acceptably? Pull to one side or the other?
Is the ride smooth and not all chattering?

 

[Dibbons]

The vehicle tracks straight ahead very well. Around a curve I thought I started to hear a some very high pitched tire squeal. The tires are new, so no wear pattern yet.

 

[///Matt]

Tracking straight, hotter on the outside, my gut says it’s got too much toe-in.

With the steering wheel straight ahead, Measure the distance between the front rims at the leading edge, and at the rear edge, the same height from the ground. If they’re not equal, there’s a concern.

 

[///Matt]

Keep in mind... the Nascar guys are doing it with laser thermometers, not palms. But yeah.

 

[Dibbons]

I'll use my laser thermo on it after my drive tomorrow. With my bare hand, it was a very obvious difference tonight.

 

[WileERobby]

It all depends whether you insert the thermometer orally or ****.

 

[moparedtn]

It all depends whether you insert the thermometer orally or ****.

Iffin it were mine and I had just put new tires on it AND I was dubious of the front end alignment, that rascal would be on an alignment rack pronto.
….which is exactly what happened to mine when it first hit the road again after a dozen years.

 

[Aeronet]

I think that's a valid way to get an idea of what's going on with your alignment. I do that occasionally. I also feel the wheels to see if the brakes are dragging.
Now you know things aren't right.

 

[Wietse]

To check toe-in you could pull a thin wire from the rear wheel, making sure it contacts both cheeks and pull it across the front wheel.
Then you measure the difference between both cheeks of the front tire, which will be different and should be different.
The measurement on the front side of the wheel needs to be around 1/8" more so the wheel stands slightly inwards in the driving direction.
Do this for both wheels and you will be very close.

Also, did you check/adjust camber? To much positive camber causes the tire to contact the road on the outside.
With the modern type radial tires a slight degree of negative camber is wanted for good drivability, 1-1.5 Deg.

 

[Dibbons]

I purchased the tires out of town on a road trip and the lower ball joints were replaced at the same time. The alignment was done also, but I was not given the final specs. This was in Mexico, so things are a little different around here, although like everyone with and older car, finding a competent alignment shop is not easy. That is way I am trying to learn this stuff on my own.

It would be cool if we had a screen on dash that constantly showed our alignment specs as we drove straight down the road, and how they change on the curves, while braking, etc. That technology does not exist ... someday.

 

[Wietse]

Watch this guy, very good way to check your toe, i have followed this and works well.


For camber and caster i used a digital spirit level, you need to make sure the car stands on a level surface, after you can adjust and check each wheel camber by keeping the spirit level agains the rim and get them to 1-1.5 Deg Negative camber. (Top of wheel facing inwards looking from the front)
Caster is harder, i just compared the Left and Right are about the same angle by keeping the spirit level against the same reference points left and right.

 

[Dibbons]

It's good to know there are ways to measure toe and camber at home. But my question now is, will the wrong caster setting cause excessive tire tread wear or is toe and camber the only critical worries for that?

 

[Wietse]

i would say toe is the biggest tire killer.

 

[Aeronet]

It's either toe or camber. There's an article on Allpar by Richard Ehrenberg about alignment specs. Remember, the factory specs are for bias ply tires.

 

[///Matt]

It's good to know there are ways to measure toe and camber at home. But my question now is, will the wrong caster setting cause excessive tire tread wear or is toe and camber the only critical worries for that?

Caster doesn’t affect tread wear much, it’s mostly about steering input and feel.

 

[Dibbons]

After a 15 minute drive today @ about 50 MPH here are the temp readings you all have been waiting for:

driver's side front tire outer tread 136 degrees inner 101 degrees
Pass side front tire outer tread 136 degrees inner 113 degrees

driver's side rear tire outer and inner tread both 98 degrees
pass side rear tire outer tread 113 inner 104 degrees

Don't know if crown of the road has anything to do with varying temperatures. Weird that right rear tire is unequal while the left rear tire is the same across the tread.

Edit--Short article attributing hot outside tread temps to not enough negative camber:
http://automotivearticles.com/123/Tire_Temps.shtml

 

[Wietse]

I think you better focus on alignment and make sure it is properly set up.
After you can measure tire temperatures again and i am quite sure it will improve.

 

[Dibbons]

I took several measurements of tread depth across the width of the tire with a millimeter dial caliper and every area that had higher temps had a little less tread depth than the cooler area.

driver's side front tread depth:
5.54 mm inside
5.3 mm outside

pass side front tread depth:
5.15 mm inside
5.0 mm outside

driver's side rear tread depth (did not follow the pattern):
this was 5.7 mm inside, 5.6 mm & 5.8 mm center, 5.9 mm outside

pass side rear tread depth:
5.6 mm inside
5.45 mm outside

 

[Dibbons]

Front and rear tires are different brands and were installed at different times. The front tires have only about 500 miles on them and the rear have between 6,000 and 8,000:

Front are Uniroyal "Pantera' (directional) not for sale in the USA:
215/70R14 96T
treadwear 520 traction A temperature A

Rear are Cornell 1000 (Pep Boys brand)
P215/70R14 96S
treadwear 300 traction A temperature B