Community Forums

timjet · 11-12-2019, 08:40 AM

My current tires are Michelin 295/80R/22.5
Due to cupping I want to replace with Hankook.
There are several choices but Hankook only makes a /75R 22.5 tire.

I guess it should be OK.
They make several steer tires in this size range. The dealer has (2) A21 295/75R/22.5.
Comments?

richard5933 · 11-12-2019, 09:00 AM

There are many good tire manufactures to choose from, and if Hankook doesn't have the tire size you need then I'd suggest looking elsewhere. Toyo is another brand that has lower cost than Michelin and has very good reviews.

Is there some reason that you are determined to get Hankook tires even though they don't have the size you need?

I'd never consider changing tire size solely to get a particular brand on my coach.

450Donn · 11-12-2019, 09:01 AM

Have you checked the shocks? Tire cupping is often times caused by excessive bouncing, which is controled by the shocks.
As for Hankook tires? They have a very good reputation. Just look and see what class 8 trucks are using.

timjet · 11-12-2019, 09:11 AM

I had the alignment checked and it's good. No bouncing.
I've been told that sometimes tires are just not good and cupping just happens. Maybe some impurity in the rubber.

Michelin's are 2x the cost of the Hankook. Are they really that much better. Apparently they weren't for me. I got 40,000 miles on these when I noticed the cupping.

timjet · 11-12-2019, 09:45 AM

Quote:

Originally Posted by richard5933

There are many good tire manufactures to choose from, and if Hankook doesn't have the tire size you need then I'd suggest looking elsewhere. Toyo is another brand that has lower cost than Michelin and has very good reviews.

Is there some reason that you are determined to get Hankook tires even though they don't have the size you need?

I'd never consider changing tire size solely to get a particular brand on my coach.

If my calculations are correct the Michelin 295/80R/22.5 have a sidewall height of 9.29 inches while the Hankook 295/75R/22.5 have a sidewall height of 8.75. IOW the Michelin's sidewalls are slightly more than .5 inche higher.

Does that make a difference?

richard5933 · 11-12-2019, 01:08 PM

Quote:

Originally Posted by timjet

If my calculations are correct the Michelin 295/80R/22.5 have a sidewall height of 9.29 inches while the Hankook 295/75R/22.5 have a sidewall height of 8.75. IOW the Michelin's sidewalls are slightly more than .5 inche higher.

Does that make a difference?

In a word, yes.

Tires come in different sizes for many reasons, and without asking the engineers there is no good way to know the specific reasons they selected the tire size they did for your coach.

The tires you're considering will likely lower the ride height slightly, and they are narrower. The result could be a decrease in the amount of tread in contact with the pavement, affecting both braking and handling. Weight capacity needs to also be thoroughly checked, as well as dual spacing.

Still not sure why you're sticking with Hankook tires if they don't have the size you need for your coach. They are not the only ones making affordable tires which are good quality.

znt1186 · 11-12-2019, 01:18 PM

https://tiresize.com/comparison/

Looks like 315/75/22.5 is what you need. Same diameter tires. Just a little over .8" wider though.

richard5933 · 11-12-2019, 02:52 PM

Quote:

Originally Posted by znt1186

https://tiresize.com/comparison/

Looks like 315/75/22.5 is what you need. Same diameter tires. Just a little over .8" wider though.

That's considerably wider. On our coach the previous owner installed 315s instead of the OEM 12R22.5 tires. Same diameter, but the extra width was about 3/4". Doesn't sound like much, but it was enough to cause the tires to rub on the air bag mounts on a full turn. Could be catastrophic. On some vehicles 0.8" is enough extra width to cause serious problems with the dual spacing on the rear tires. Plus, odds are the current wheels are not wide enough for the 315s, as most of them require 9" wheels now.

If the proper size tires were not being manufactured by many other companies I'd understand the need to change sized. As it stands though, I don't see why the need to find a tire that will sort of/maybe work when the actual correct size tire is out there.

Gary RVRoamer · 11-12-2019, 03:35 PM

Quote:

I've been told that sometimes tires are just not good and cupping just happens. Maybe some impurity in the rubber.

Pardon me, but HOGWASH! Cupping happens from a bouncing or wobbling tire. Bad shocks (if you drive on rough roads), bad wheel bearings, bent wheel, excessive runout, etc. Something is wrong and changing tires doesn't fix it.

If you want good quality 295/80R22.5's, choose a brand that has them. Toyo has an excellent one (M144), also BF Goodrich, Bridgstone, Firestone, and yes, even Hankook as well (DH05).

Gary RVRoamer · 11-12-2019, 03:39 PM

Quote:

I've been told that sometimes tires are just not good and cupping just happens. Maybe some impurity in the rubber.

Pardon me, but HOGWASH! Cupping happens from a bouncing or wobbling tire. Bad shocks (if you drive on rough roads), bad wheel bearings, bent wheel, excessive runout, etc. Something is wrong and changing tires doesn't fix it.

If you want good quality 295/80R22.5's, choose a brand that has them. Toyo has an excellent one (M144), also BF Goodrich, Bridgstone, Firestone, and Continental & Goodyear too.

Dennis4809 · 11-12-2019, 06:45 PM

Quote:

Originally Posted by timjet

My current tires are Michelin 295/80R/22.5
Due to cupping I want to replace with Hankook.
There are several choices but Hankook only makes a /75R 22.5 tire.

I guess it should be OK.
They make several steer tires in this size range. The dealer has (2) A21 295/75R/22.5.
Comments?

Putting on 6 A21’s tomorrow.
Dennis

richard5933 · 11-12-2019, 07:19 PM

Quote:

Originally Posted by Dennis4809

Putting on 6 A21’s tomorrow.
Dennis

Have you confirmed that they will work without creating any problems?

Still not sure why the insistence on putting on the wrong size tires.

timjet · 11-13-2019, 03:02 AM

Quote:

Originally Posted by Gary RVRoamer

Pardon me, but HOGWASH! Cupping happens from a bouncing or wobbling tire. Bad shocks (if you drive on rough roads), bad wheel bearings, bent wheel, excessive runout, etc. Something is wrong and changing tires doesn't fix it.

If you want good quality 295/80R22.5's, choose a brand that has them. Toyo has an excellent one (M144), also BF Goodrich, Bridgstone, Firestone, and Continental & Goodyear too.

Thanks Gary I was expecting that.

Richard; both the Michelin and Hankook are 295's which is the width in mm, so they are the same width, just the side wall height is different.

I still don't know why I've got the shoulder depression wear, according to the chart Gary referenced it is caused by mis alignment, loose wheel bearings, bad shocks, or wheel out of balance. Since I had the alignment checked last week I'm going to rule out alignment and bearings (I had the wheel seal replaced on the wheel 6000 miles ago and the tech said the bearings were good).

In another post someone said unless I'm getting bouncing I can rule out shocks. I'm not getting bouncing but the cost of shocks are cheap compared to tires and I don't know when they were last replaced on this 12 yo coach.

Richard, you make a good point about the reason's for staying with the same tires. Hankook does not make 80R tires so I'm reconsidering. Michelin are what's on them now. They are 2x the price of the Hankook but I'm going to consider Toyo and some other brands.

I know some folks have some very pointed opinions about tires but are Michelin really worth their price? I will pay their price if I'm getting a better product, I'm just not sure I would be getting a better product.

richard5933 · 11-13-2019, 04:29 AM

My impression, after researching and reading countless reviews and tire industry blogs, quality is about the same across the spectrum on the top-tier tires. Each has had its problem moments, but generally speaking it's more a matter of personal taste than anything else when choosing between top-tier tires. Get into the lower-quality tires and less expensive imported tires, and all bets are off in my book.

With that said I have no doubt that you can find the proper size tire, from a top-tier brand, at a price that will be comparable to the Hankooks.

Important consideration would be your rim width. The Hankook's specifications state 9" rim, the Michelin state both 8.25" and 9". What rims are on your coach? Have you confirmed that whatever tire you're considering is rated for your rims?