Explorers and tire problems


#1

before all the hoopla about explorers and tires hit the news, I had noticed many explorers (10 or 15) riding down the road with one of their front wheels having a severe tilt, neg. camber like.

was this ever considered as part of the problem?


#2

I don’t know if it was considered officially but odds are some crashed were due to the camber problem. Negative camber is usually caused by worn ball joints which will wear the tire off on the inside edge. Eventually the tire (and maybe with underinflation involved) gives up and the tire gets all the blame.

Just a few days ago a Tahoe passed me doing 70 MPH with about 5 degrees of negative camber on the RF wheel and I commented to my wife that someone else has a death wish.


#3

I don’t recall the camber being the problem, more to do with the tires themselves although worn or incorrectly maintained suspensions can play a role.


#4

yeah I never heard the problem mentioned, but I certainly saw many explorers with that condition before it all came out in the news


#5

I remember most of the accidents investigated were due to overloading and under-inflation. Pilot error!


#6

Ditto. Speaking of underinflation, I was behind 2 farmers yesterday pulling an implement trailer with what looked like a pair of 155 X 13 tires on it. The trailer had a heavy 24 foot long combine header on board and the left rear of that trailer looked like it had about 10 pounds of air in it.

That trailer was wandering all over the roadway and that is the reason one sees a lot of trailers on the roadside here; overloaded and underinflated tires.


#7

Re. explorers and tire problems.
For a while I thought we were talking about Marco Polo and Leif Ericson.


#8

I don’t recall a camber problem as having been identified as a contributor. This particular situation was analyzed perhaps more than any other problem in the history of automobile safety. Countless engineers and consultants got very well paid by the lawyers, by Ford, and by Firestone to perform endless analysis, testing, and testimony, more than any other crash investigation ever. It seems that camber would have been highlighted as a contributor if it had been.

I seem to recall that it was isolated down to Ford having made a tire pressure recommendation in order to compensate for a known design-caused instability that was outside of the recommendations made by Firestone for the tires Ford was using on the vehicle.


#9

tyre?


#10

Tyre is the English spelling. I like it.
I didn’t see it anywhere in this thread, however. Did I miss it?


#11

I think the recommendation was 25 PSI or something like that; too low for a heavy vehicle. Factor in that most drivers are not even going to maintain that 25 figure and the underinflation and subsequent overheating and sidewall failure is pretty much a given.

It’s also possible that worn ball joints contributed to tire wear and blowouts which led to crashes. Odds are the mangled wreck was chalked up to a bad tire and it went no further than that.

Tyre reminds me of Mr. Meehan who hasn’t posted in a while. Hope he’s doing alright.


#12

I was thinking of the city of tyre…

i just remember seeing many crooked tires on explorers before all the controversy happened.


#13

Any vehicle with that much negative camber will eat up tires very quickly. My late father (who lived in another city) used to get his car serviced every year before vacation.
One year he had a new set of tires installed, oil change, and alignment performed.

When he arrived at his destination about 800 miles away my parents spent the night with relatives.
The next morning when they walked outside my dad’s brother in law made a comment about a tire blowing out. The car was parked with the wheels turned out and the BIL had seen steel showing.

Two brand new tires ruined in 800 miles and all because the shop never did the alignment with both camber and toe way out. The shop where they sorted this out stated that all of the bolts on the suspension were lightly covered with rust and showed no signs of ever being touched.
That’s how quickly new went to junk.

When he returned I took the paperwork and went to the shop to let them know about it. They refunded the cost of the 2 tires and the alignment. Dad was probably lucky that one of the fronts did not blow out on him at speed on the interstate.


#14

A sagging twin I-beam front suspension will produce negative camber:


#15

All independent suspension systems are designed to produce negative camber when the wheel goes above the static position. Because of the arcs involved in suspension geometry, if the wheel were to move straight up and down the centerline of the contact patch would move in and out, creating a constantly changing track. This would create unstable handling and premature tire wear due to “scrubbing”. By tilting the wheel enough to keep the track stable as the wheel moves throughout its range, the track is kept constant and the problems of a varying track are avoided. Normally, this works beautifully, but if the suspension becomes weak and sags it results in excess negative camber.

You can readily see this concept especially in suspension with both lower and upper A-frames, like on small pickups. The upper A-frame will be shorter than the lower one, and if you follow the travel of the ball joints through their arcs you’ll see how it tilts the wheel. Imagine both A-frames being the same length and you’ll be able to easily envision the wheel moving back and forth and the track changing.


#16

If I had owned one of those Ford Explorers (no chance BTW) I would have probably been OK. I almost always inflate my tires to 32psi regardless of what’s listed on the vehicle placard. I always have and have had very few tire problems. I’m not suggesting anyone else do that and all my vehicles have been passenger cars or trucks. The only exceptions were my motor homes but they are a different animal entirely.


#17

According to IIHS - They did testing on the Ford BEFORE there was a problem…and they noticed a problem with the stance of the Explorer. Their biggest concern was it was too narrow.

The whole thing with Firestone tires and the Explorer was NOT just the tires…but there were several factors. The tire pressure, the tires themselves could not hold up to the heat, and the fact the Explorer was too narrow and in an emergency situation they had a high probability of rolling over.

The second generation of the Explorer - Ford widened the wheelbase by at least 3". IIHS tested the new design and found it MUCH better.


#18

the same mountain bike said: “…I seem to recall that it was isolated down to Ford having made a tire pressure recommendation in order to compensate for a known design-caused instability that was outside of the recommendations made by Firestone for the tires Ford was using on the vehicle. …”

Sorry, but the conclusion was that the tire had some design issues that were aggravated by how the rubber was processed at one particular plant. There were also side issues about aging properties of tires that were never resolved, but the inflation pressure issue was NOT cited as a problem - although followup designs by Ford and pretty much every SUV manufacturer added load carrying capacity (usually by increasing the tire size).

OK4450 said: “…I think the recommendation was 25 PSI or something like that; too low for a heavy vehicle…”

It was 26 psi, but that was enough to carry the rated load of the vehicle - as per common practice at the time.

As an illustration, would it make you feel better if they had used 35 psi and but used a smaller sized tire? They did that at one point in time without apparent issue. Other tires were also on the vehicle - also without issue. It was only that one tire from the one particular plant that was an issue.


#19
OK4450 said: "........I think the recommendation was 25 PSI or something like that; too low for a heavy vehicle....."

It was 26 psi, but that was enough to carry the rated load of the vehicle - as per common practice at the time.

My 90 Pathfinder tire pressure recommendation was also 26psi. They were the same size vehicles…The Pathfinder didn’t have these problems.

Also Firestone was not the only tire used on the Explorer. And other tires set at the same psi were not experiencing the same problems. It had a lot to do with the heat.


#20

i also remember ford airing there tires down i think it was to meet rollover specs. @mikeinnh there may have different amount of plies compound ect in there tires either way there was some kind of miscommunication between ford and firestone. firestone designed a tire to be used a way that ford wasnt using it. maybe these differences kept other tires from having the problems but either way 26psi seems pretty low for a heavier vehicle