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Discussion Starter · #1 ·
You guys have probably seen me complaining about ride quality / road vibrations in other threads. Well I, and the mechanics, have checked all kinds of stuff and are pretty sure it’s just the tire I’m using, and I want to run this by you guys before I buy something else I’ll regret…again.

Current configuration:
Kenda Klever AT2 235/75/15 (29.5”?)
Rear coilover shocks that give ~1” lift
Torsion keys lifted a little, approx 4 full turns out from max

Previous configuration with acceptable ride comfort:
General Grabber ATX stock size tires
Everything else stock height

The kenda AT2 tires are closer to a mud tire from what I am told, very knobby and lots of space. The General ATX tires have your standard AT tire look to them, and never gave me a problem.

now my question is, should I buy the general grabber AT again, or is there another less aggressive AT tire I would like?

And my most important question, should I buy them in the current size (29.5”) as the Kendas, or just return everything to stock? I have heard tire size itself can contribute to road vibration, but I’m not sure as I am a noob, and I also know the coilovers and torsion lift could do. My mechanic thinks it’s the tread for sure though, and thinks same size will be fine.

FWIW, I like the extra lift but don’t find it necessary like I thought I would. My “off roading” is usually rough dirt roads, and snow. Nothing crazy.
 

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I have General at’s ride. Is stable and not noisy. My tires are stock size as is all my suspension. You can buy a better tire, but not one that is quieter. jmo.
 

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I once had some Goodyear Wrangler ATs on an S-15 that I liked. I always thought they were going to lose traction braking on wet roads, but never did. Awesome dig in deep snow in both take off and stop. I don't recall them being overly noisy or a rough ride.
When I replaced them, I used a set of Goodyear Wrangler all weathers that were very disappointing. I was skidding in rain and snow.
 

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2000 Lifted 4x4 Astro 92 V8-350 Shorty
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I am running commercial series LT245/70-17 Firestone Transforce HT2 tires...
"HIGHWAY TOURING" 10-ply Load-range E, 30.6" diameter.
Common on commercial vehicles, motor-homes, etc.
They come in more practical sizes too I think.

I LOVE THESE TIRES!!
My cat likes them too.
Tire Wheel Car Automotive tire Vehicle


They ride smooth as glass (at 60psi) and dramatically improved my fuel mileage when I switched from 31" BFG AT's. They are super rugged commercial series 10ply tires, yet give me a GREAT smooth ride with their highway touring tread pattern. They serve me just fine off road too. BEST OF BOTH WORLDS. No wander or flex, they are firm, steady, quiet, and drive straight... I highly recommend.

But if you need something that "looks" cool with a rugged tread pattern, then these aren't for you.
I like that they give me a stock stealth look while still being a serious LT tire.
Not exactly cheap, but well worth it.

 

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Discussion Starter · #5 ·
What about size specifically? I’m definitely going less aggressive, but does a larger size itself impact the ride quality that much? I’m just not sure if I should go back to stock tire size, or stick with the 29.5”. Don’t want to regret that aspect! Of course, I have to factor in that the lift needed for those tires may also exacerbate ride quality, but my mechanic says it’s totally the tread design, and not to worry about size. Just want more opinion before I buy some.

Here’s a pic of the current tire.
 

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my mechanic says it’s totally the tread design, and not to worry about size. Just want more opinion before I buy some.
Your mechanic is 100% correct... tread design totally affects ride, not necessarily size (within reason).
Size just needs to fit.

Personally, I would NEVER run tires like you've pictured (that's what was on my van when first purchased and was the first thing changed) unless I had a rock crawler and primarily drove off road where ride quality doesn't matter. But since I do 99.9% of my driving on highways and pavement, I would want an appropriate tire for the type of driving I do MOST. I also drive mine every day, and travel with it. For the rare times I might have to drive off-road, my LT tires do just fine. I've found what works GREAT for me!

If it's looks & appearances you are going for.. then ride quality becomes less important.
There are however less aggressive AT tires that do quite well also.

As far as tire size.. it should "match" the lift application. At this point, if I ran stock sized tires on my lifted van, they would look silly and ridiculous. But I'm no fan of "oversized" either... unless it's some "specialty" application.

Why not do what I did.. go down one size and get a less aggressive AT tire tread. It will probably look just right, and ride so much better. For me everything improved. One inch less tire is actually only 1/2 lift difference. 29" tires seems to be the magic number with moderate to fair amount of lift.

Here's what a stock FULL-SIZED tire looks like on my lifted van.. LOL
But probably fine with only a small lift.
Wheel Tire Automotive parking light Car Vehicle


Everyone is different.
I just gave you my personal preferences, which is ride quality.
You have to do what works for you.
 

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Mechanic is correct -- tread design makes much more of a difference in ride quality. Going too big might bring your engine out of it's optimal power band -- but shouldn't affect the van being "darty" or "harsh".

That being said -- while new and less aggressive tires will help -- you might want to go smaller and turn down your torsion keys as far as possible -- I reckon that'll make a much larger difference in ride quality, even with the tires you already have.

Worth a try -- as it'll only cost you an alignment -- seems cheaper than a set of 4 new tires.
 

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Discussion Starter · #8 ·
Your mechanic is 100% correct... tread design totally affects ride, not necessarily size (within reason).
Size just needs to fit.

Personally, I would NEVER run tires like you've pictured (that's what was on my van when first purchased and was the first thing changed) unless I had a rock crawler and primarily drove off road where ride quality doesn't matter. But since I do 99.9% of my driving on highways and pavement, I would want an appropriate tire for the type of driving I do MOST. I also drive mine every day, and travel with it. For the rare times I might have to drive off-road, my LT tires do just fine. I've found what works GREAT for me!

If it's looks & appearances you are going for.. then ride quality becomes less important.
There are however less aggressive AT tires that do quite well also.

As far as tire size.. it should "match" the lift application. At this point, if I ran stock sized tires on my lifted van, they would look silly and ridiculous. But I'm no fan of "oversized" either... unless it's some "specialty" application.

Why not do what I did.. go down one size and get a less aggressive AT tire tread. It will probably look just right, and ride so much better. For me everything improved. One inch less tire is actually only 1/2 lift difference. 29" tires seems to be the magic number with moderate to fair amount of lift.

Here's what a stock FULL-SIZED tire looks like on my lifted van.. LOL
But probably fine with only a small lift.
View attachment 286687

Everyone is different.
I just gave you my personal preferences, which is ride quality.
You have to do what works for you.
yeah I think I have learned my lesson. I saw a lot more off roading when I did this, and I realized I just don’t need any of it.

with your tires, aren’t they a little stiff?

im leaning towards the general grabbers since I know they didn’t give me a problem in the past, yet still has some AT capability.

I recall in another thread you said that larger tires could exacerbate ride comfort though. That’s part of why I am not ready to pull the trigger on the 29” tires, and considering getting the stock size to just undo everything I have done to affect ride comfort.

plus, with the 29” tires, I may have to rely on some torsion lift and MAYBE the rear coilovers for rear lift, which affects ride quality even if the tire size itself doesn’t.

Mechanic is correct -- tread design makes much more of a difference in ride quality. Going too big might bring your engine out of it's optimal power band -- but shouldn't affect the van being "darty" or "harsh".

That being said -- while new and less aggressive tires will help -- you might want to go smaller and turn down your torsion keys as far as possible -- I reckon that'll make a much larger difference in ride quality, even with the tires you already have.

Worth a try -- as it'll only cost you an alignment -- seems cheaper than a set of 4 new tires.
I kind of did try that. I lowered a good 4 full turns. I suppose I could go lower, maybe put normal shocks on the rear also. It’s already out of alignment from trying to lower it, so I guess I could go even lower. I don’t notice a difference though so I have my doubts. But maybe I can go even lower and see.
 

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I kind of did try that. I lowered a good 4 full turns. I suppose I could go lower, maybe put normal shocks on the rear also. It’s already out of alignment from trying to lower it, so I guess I could go even lower. I don’t notice a difference though so I have my doubts. But maybe I can go even lower and see.
Gonna be hard to know how it drives if you crank the bars without an alignment -- especially if you're going 4-6 turns or more. A bad alignment will make a vehicle much less enjoyable to drive--especially if it's pushing around heavy, off-road style tires.

Too little toe -- too little caster -- and it's going to feel squirrely and have terrible road manners -- so moving the keys without an alignment is going to be a losing battle IMO -- you're fixing one thing and screwing up a much more important thing in the process.

Honestly -- I'd drop it as low as you'd like to drive it and go for an alignment. Maybe find a tire shop that is willing to align it -- tell them if you don't like it -- you're gonna buy new tires. They might cut you a deal on the second alignment or tires if you're honest with 'em about why you want the first alignment now.
 

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Lift and suspension stiffness will affect body roll while cornering and hardness of hitting bumps. Extra height will give you more inclination for body roll but will clear you of bottoming out on hard bumps. Stiffening the suspension will reduce the body roll some, but make the bumps a harder impact.
Alignment can affect tracking of course. If a wheel is aligned to go another direction than the rest, then you will be fighting that in your steer. This can cause vibration.
Tire tread design is the biggest factor that affects road noise or tire sing. Off road tires tend to make a good hum going down a paved road while road tires more of a swish. This can also affect vibration as running down a road on essentially tractor tires will create vibration. Street tires are designed for smooth rolling and quieter rides.
Air pressure can affect comfort as well as being too high will create a harder ride and being too low will be spongy and swishy. Either way can affect noise.
I'm sure I don't need to mention balance, but I did.
Often there are places that sell used tires recovered from salvage vehicles, depending on where you are. They are usually heavily discounted because the won't have a mileage warranty, but you can find sets of four in really good condition for less than half the price of new. These places are great for finding a replacement for a blown tire, getting a set of tires on a budget, and perhaps in your case, testing different designs without throwing away as much money if you don't like them.
You could also try out your new set, and if you don't like them, sell them off. Either way you won't lose the whole amount if you are not happy.
 

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Your mechanic is 100% correct... tread design totally affects ride, not necessarily size (within reason).
Size just needs to fit.

Personally, I would NEVER run tires like you've pictured (that's what was on my van when first purchased and was the first thing changed) unless I had a rock crawler and primarily drove off road where ride quality doesn't matter. But since I do 99.9% of my driving on highways and pavement, I would want an appropriate tire for the type of driving I do MOST. I also drive mine every day, and travel with it. For the rare times I might have to drive off-road, my LT tires do just fine. I've found what works GREAT for me!

If it's looks & appearances you are going for.. then ride quality becomes less important.
There are however less aggressive AT tires that do quite well also.

As far as tire size.. it should "match" the lift application. At this point, if I ran stock sized tires on my lifted van, they would look silly and ridiculous. But I'm no fan of "oversized" either... unless it's some "specialty" application.

Why not do what I did.. go down one size and get a less aggressive AT tire tread. It will probably look just right, and ride so much better. For me everything improved. One inch less tire is actually only 1/2 lift difference. 29" tires seems to be the magic number with moderate to fair amount of lift.

Here's what a stock FULL-SIZED tire looks like on my lifted van.. LOL
But probably fine with only a small lift.
View attachment 286687

Everyone is different.
I just gave you my personal preferences, which is ride quality.
You have to do what works for you.
I just put 17" wheels on my rig and the tires that with it are 265/70 17 I am thinking it might be a bit big. Did you have to cut your wheel wells for the 245s?
 

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Yes you pretty much ALWAYS need to trim something with any larger tires.
I had LT265/70-17's originally (31.5") tires.
They fit fine (no rubbing) with trimming.. but I'm also lifted 8".
I didn't like them, and after a few years went down a size to 245/70-17 (30.5")
It is a much better fit now for me, looks better, drives better, improved fuel economy.
They will still require some trimming (see post #4 above).
29" is a good size (with modest lift).. but still going to need to trim
 

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Discussion Starter · #13 ·
Yes you pretty much ALWAYS need to trim something with any larger tires.
I had LT265/70-17's originally (31.5") tires.
They fit fine (no rubbing) with trimming.. but I'm also lifted 8".
I didn't like them, and after a few years went down a size to 245/70-17 (30.5")
It is a much better fit now for me, looks better, drives better, improved fuel economy.
They will still require some trimming (see post #4 above).
29" is a good size (with modest lift).. but still going to need to trim

Looks like my kendas are 29". I did have to trim the bumper, and then bang the pinch seam with a sledge, to prevent rubbing

now that we're on this topic...I wonder...is a lift necessary for the 29" tires? I kind of want to lower the torsion to stock height.
 
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