16" Goodyear vs 17.5" Sailun Tires

After installing the new tires, I did notice one change...

The Sailun tires are shorter, thinner than the Goodyear's.

BUT, they are more Ply (16 vs 14). And the treads were deeper.

The distance between the front and rear tires are slightly more.

I could not tell any difference in pulling or sway in the limited test-drive. Maybe later when long-hauling.

Here are pics of the difference:

Are they the same size?

Are they the same size?

No.

The Goodyear's were 235/80R16 (14-Ply)

The Sailun are 215/75R17.5 (16-Ply)

The pictures show the differences...

I thought Ron said the G and H's overall diameter (tire and wheel) was essentially the same. Why he said we could retain the G tire and wheel as a spare when we upgraded to the H tires.

I thought Ron said the G and H's overall diameter (tire and wheel) was essentially the same. Why he said we could retain the G tire and wheel as a spare when we upgraded to the H tires.

Height wise, I would consider them pretty close. Maybe a 1/2" difference. If you have a flat, the G rated tire would be OK to get you to a repair center.

Having shown the pictures, I don't know for sure if there is a difference once weight is applied. 16-Ply would be stronger that 14-Ply.

I'm going to keep the G-Tire as a spare. No sense in spending the extra if not required. It will just sit under there and dry rot before it has to come out...

Yep, when I upgraded to the 17.5s from Ron, I kept my 16" G Spare Tire

Rob, you of all would notice any difference in tires in the handling. Was there any ?

Rob, you of all would notice any difference in tires in the handling. Was there any ?

Vaughn, I changed to the 17.5s just before leaving Florida heading to MoRyde and the Redwood Rally last summer.

The ride was noticeably more solid and stable with just the tire upgrade.

After visiting MoRyde and having the IS, Disc Brakes and MoRyde Pin Box installed along with the upgraded 17.5 Tires, my ride, stability and handling is fantastic.

Things do not move around inside my coach near as much and when setting up and leveling my rig, no more suspension popping and groaning as the level up system does its thing.

Are they the same size?

No.

The Goodyear's were 235/80R16 (14-Ply)

The Sailun are 215/75R17.5 (16-Ply)

The pictures show the differences...

Ah, I guess a 238/75R17.5 puts you in a Load Range I.

The 215/75R17.5 is slightly smaller than the 235/85R16 and the same size as the 235/80R16. The sizing differences between these 3 tires is not meaningful with the exception of load capacity. The 4800 lb. capacity of the 215/75R17.5 is more than adequate for the Redwood.
There is a 235/75R17.5 H made that is the same size as the 235/85R16 only it has a 6,000 lb. load capacity. This is overkill but available.

I am sure this is obvious, but... why do we want to go from a 16 to a 17.5 tire?

Reserve load capacity. Your car, SUV, Light Truck all have 20%-40% reserve load capacity. If you add max load capacity of all tires/ by the GVWR you get the % loaded. The difference in 100% is reserve load capacity.
We know that on our personal vehicles we seldom load anywhere close to GVWR yet on our trailers we routinely load 90%+ of the tire capacity, 100$ of the time.
If we want our trailer tires to be as dependable as the tires on our other vehicles, we should load them similarly.
If you have a wheel position that smart weighs 3,400 lbs. and your load range G tire has a capacity of 3750, you are 90% loaded, 100% of the time. I believe the 3,400 lbs. is probably a good average although some owners are reporting over 3,600 lbs.
If you put on a 17.5 H at 115 psi. you would have a load capacity of 4,500 lbs. or only 75% loaded. I run between 110-115 on the 17.5's on my 38GK.

Reserve load capacity. Your car, SUV, Light Truck all have 20%-40% reserve load capacity. If you add max load capacity of all tires/ by the GVWR you get the % loaded. The difference in 100% is reserve load capacity.
We know that on our personal vehicles we seldom load anywhere close to GVWR yet on our trailers we routinely load 90%+ of the tire capacity, 100$ of the time.
If we want our trailer tires to be as dependable as the tires on our other vehicles, we should load them similarly.
If you have a wheel position that smart weighs 3,400 lbs. and your load range G tire has a capacity of 3750, you are 90% loaded, 100% of the time. I believe the 3,400 lbs. is probably a good average although some owners are reporting over 3,600 lbs.
If you put on a 17.5 H at 115 psi. you would have a load capacity of 4,500 lbs. or only 75% loaded. I run between 110-115 on the 17.5's on my 38GK.

Exactly why we recently changed ours...Thanks Ron (Titan Guy)!

We were at 97% on one side and 93% on the other side. This is BEFORE we moved in full time. Now that we have "extra" on board, we would have been at the 100% mark. This puts us back in a comfortable range of 80% (+ or -).

And IF one were to blow a tire because they are so close to capacity with G tires, then they might also experience $8000 in repairs to the sides of the RV from the tire that disintegrates and shreds the the bottom and sides. Hopefully if it happens, it won't be on the same side as propane lines. But it would probably would be that side since that is usually the same side as the refrigerator and stove.

This was money well spent.

Vaughn,

I agree with Rob. Upgrading to the Goodyear G114 17.5" tires and aluminum wheels made my Redwood ride much better. Combine that with the MoRyde IS system and the ride is IMO more comfortable, stable and safer.

There was a time when the G614 wasn't proving out to be very reliable either, so folks started jumping to the 17.5. I think Goodyear got their stuff together as I haven't heard anything for a while.