Again, It's NOT the tread design causing the problem. It's the sidewalls that are not stiff enough. I used to litterally watch them flex when the van was swaying side to side during lane changes. It was like one of those fire trucks that have rear steering. The rear end had a mind of it's own during any kind of steering changes. It was so scary I had to end my work week early just to get home and get the tires removed so I could go back out and earn some money safely.
Again, It's NOT the tread design causing the problem. It's the sidewalls that are not stiff enough. I used to litterally watch them flex when the van was swaying side to side during lane changes. It was like one of those fire trucks that have rear steering. The rear end had a mind of it's own during any kind of steering changes. It was so scary I had to end my work week early just to get home and get the tires removed so I could go back out and earn some money safely.
The only reason I ask is that I've got an E150, and even loaded with 7 passengers (about 1400 lbs) plus a few hundred lbs of luggage, I haven't really felt any unsafe side to side movement in my sidewalls, which are *only* P235/75 x 15 XL car-type tires (with 41-42 lbs of air in them).
I'm guessing that D or E tires of almost any brand have to have a HELL of a lot more sidewall stiffness than my tires (which I recall have only two sidewall plies--Michelin LTX M/S), which is why I was thinking that squirming tread blocks could be an issue. A basic E250 is only a few hundred lbs more than my van (maybe less when I consider that I have full glass and a conversion interior), although they do sit higher...
The sidewall height is the key to the movement. The 245/75/16s are tall tires and with all that sideways motion the tires just rock back and forth unless they are built to handle it even with the 70 psi I run in them. I have a set of E rated Kuhmos on there now and they do a great job at controlling it. Plus with it being an extended Van I have extra mass back there to get things moving. hahaha
Sorry guys, I've not checked this site in over a month. Also not been getting any email notification of your replys, must be not enough cookies (or is it brownies).
I'm convinced now that Jethro's theroy is spot on, what else could have changed? I went back to the Ford dealer and had them see what tire size the computer was recognizing (my mechanics idea) and it's set up from the factory for 245/75/16's which is the bigger tire I put on after wearing out the stock Firestone 235/75/16's.
Anyway, while driving through the mountains this wk/nd I was coming down a twisty hill and going as fast as I felt I could safely in a van and what comes flying up on my rear wanting to pass, but another E250.
If it wern't for 1k miles on these tire now I'd return them but I doubt now they would take 'em back. So once there worn out I'll go with one of Jethro's suggested brands.
A bigger sway bar's still in my future along with better shocks, but for now I really think the poor handling's in the rubber.
Sorry guys, I've not checked this site in over a month. Also not been getting any email notification of your replys, must be not enough cookies (or is it brownies).
I'm convinced now that Jethro's theroy is spot on, what else could have changed? I went back to the Ford dealer and had them see what tire size the computer was recognizing (my mechanics idea) and it's set up from the factory for 245/75/16's which is the bigger tire I put on after wearing out the stock Firestone 235/75/16's.
Anyway, while driving through the mountains this wk/nd I was coming down a twisty hill and going as fast as I felt I could safely in a van and what comes flying up on my rear wanting to pass, but another E250.
If it wern't for 1k miles on these tire now I'd return them but I doubt now they would take 'em back. So once there worn out I'll go with one of Jethro's suggested brands.
A bigger sway bar's still in my future along with better shocks, but for now I really think the poor handling's in the rubber.
...thankfully you didn't drive off a mountain curve and kill yerself...
As tires wear, they will become more "solid" in terms of handling in terms of the tread part of the equation--the blocks become shorter and stiffer. So keep what you've got aired up to a nice high pressure (maybe in excess of the mfr's spec, but within the max rated pressure of the tires) to keep the sidewalls as stiff as possible, and drive safely.
Moving from a 235 to a 245 on the same rim size *will* cause a given tire to flop around just a bit more--and that may be part of what you were/are feeling--I've put 255/70's on vans and trucks in place of the 235/75's and in general, they will move around a bit more on the rim. And you went a bit taller as well.
If you went to a wider rim, it would effectively stiffen up the sidewall a bit via the geometry of the tire (and it would hold a bit more air, theoretically have a slightly higher load capacity).
It's def. funny how some tires flex more than others. For me I just didn't feel safe with those swaying tires and demanded them be replaced. Once I found one that didn't do it I stuck with it for several sets. Back when the discontinued the Steeltex ones I was like WTF am I gonna do now.
I found out that the Toyo H/T Open Country is a good one with very little sway.
Back here kicking a dead horse I know but she's still knocking down the damn barn doors.
Since my last visit here I've had the van back to the original tire dealer who as it happens just got a brand spanking new $40K alignment machine and not being too eager about taking my now used Cooper Discoverys back said let's try an alignment. The alignment was damn near right on but....the driver-side tie rod was shot so we replaced it. We also replaced the front sway-bar bushings just cuz they looked worn. I took it out for a test ride and sure enough the front end "wandering" was gone but the rear still swayed in a tight turn. He said OK, let's try another brand tire but all he had in stock was Hankooks so we put a set on. At first I thought it was better but then I went through a down hill off-camber turn on the interstate and nearly lost my lunch.
Now my delema is this. He can get the Michelin LTX's and pro-rate the difference from my now used Hankooks which would be around $300 (or) I could spend the same on a good set of Bilstien shocks.
So which way is my money better spent cuz it's one or the other, not both...I'm going broke on this damn problem.
The Bilstiens are not gonna fix the faulty tires out back, trust me.
Either just swap out the rear Hankooks for the Michelins (150 bucks) or keep the rear Hankooks and get 2 replacement Michelins for the rear. Then re-use them later when the fronts need replacements. Problem solved.
The Bilstiens are not gonna fix the faulty tires out back, trust me.
Either just swap out the rear Hankooks for the Michelins (150 bucks) or keep the rear Hankooks and get 2 replacement Michelins for the rear. Then re-use them later when the fronts need replacements. Problem solved.
I hear ya, but now that the tie-rods replaced and the steerings is as it should be I can feel the sway starting in the front, as if it tucks (if you've ever ridden a motorcycle you know the feeling) and thought the suspension in front might still be part of the problem.
I hear ya, but now that the tie-rods replaced and the steerings is as it should be I can feel the sway starting in the front, as if it tucks (if you've ever ridden a motorcycle you know the feeling) and thought the suspension in front might still be part of the problem.
Do consider what shocks do, though...they simply slow down the movements of the suspension. If the sway is kind of instantaneous, maybe shocks will make a diff, but it the van sways even after the suspension "sets in" the shocks may not matter as much.
How's about the wider rims we were talking about?
Michelin LTX's have been great tires for me in the 235/75 x 15 XL size, and I know Ford uses them as OEM on their bigger vans in the higher load ranges. But they use Hankooks as well I think.
If the Hankooks are really that bad then you will just have to bite the bullet and spring for the Michelin upgrade. I got lucky cause when this happened to me I went back to the tire shop and demanded they take those crappy tires back. They are not safe and should be labled NOT FOR USE ON FORD VANS!!!!
I just replaced the original Hankooks on my '05 E-350 with Goodrich and the handling got sloppy like reported above. The Hankooks were far better. The 'book' calls for 60 front, 80 rear, but if I put 80 in the front too, things are much, much better. I can't afford another set of tires now, so I'm gonna see if I can just get used to the new ones.
After months of head-scratching, cussing and belly-aching I got this gremlin figured out.
I went (on a tip) to the best alignment shop around and they found what the other shop missed. My camber on the front right wheel was an entire degree out. The only reason it wasn't pulling to that side like crazy was because the caster on that same side was also out conciderably but in an opposing direction.
Not only was this an alignment issue all along but apparently my van was supposed to come standard from the factory with a rear swaybar and did not. The dealership is calling it a fluke but says it does happen. I'm working with Fords customer service to try and get one at their cost next week. My tires, shocks and now alignment are all fine. The understeering feel and 90% of the sway are gone. The rear swaybar should take care of the rest. Thanks everybody for all your replys.
Oh and Jeffnick, you live in my old hometown dude!
I went (on a tip) to the best alignment shop around and they found what the other shop missed. My camber on the front right wheel was an entire degree out. The only reason it wasn't pulling to that side like crazy was because the caster on that same side was also out conciderably but in an opposing direction.
Thanks for the info.
Did your old tires show any signs of irregular wear?
Join Our Site - Its free, quick and easy!
