Community Forums

gundog · 05-08-2012, 05:59 PM

I have an 06 keystone couger 32ft. I had a pretty bad blow out not long ago and want to upgrade my tires. Based on information on this forum I would like to go from my 225/15s to 235/16s. Will they fit. Thank you

wingnut60 · 05-08-2012, 07:46 PM

What is the distance between tires now? You will be 1" closer with 16s. Check the listed diameter on the tire mfg website, and remember to get proper wheels that will take 80psi if you go with load range E. If you do some homework, you may find a 16" tire that is the same diameter as the 15 was due to aspect ratio---85/80/75/70 etc.

If you want some good info, call trailertiresandwheels.com and talk to Scott about what will fit, and he ships all over the US.

Joe

gundog · 05-08-2012, 07:58 PM

Thanks, I had read several posts on this issue, the 15inch tires are just to lite for my 9300# dry weight trailer. The recommendation was, 1. up grade to 16s and 2. get a set of maxiums. My trailer will be out of the shop tomarrow and the tire shop have my tires waiting to install. They just look alot bigger,

Groveite · 05-09-2012, 06:38 AM

I had the same problem with my old cougar....went thru the original D's (Chinese built) then went with the same 15's but in E range and finally did what I shouold have done and ordered a set of 16" rims and 4 Cooper LT E range tires (225/75/16) and NO more problems. An expensive solution but the only one I could see. Fit was no problem at all and the unit towed better.
Ian

Arch Hoagland · 05-09-2012, 08:25 AM

I think you are making a good move. On the trailer I had two of the original new tires blow out...at the same time. In the middle of Nevada at that!

Cheap OEM tires are the weak link on travel trailers as far as I'm concerned.

chief02 · 05-09-2012, 08:28 AM

if your moving up to a 16" tire, why not move to a LT?

FastEagle · 05-09-2012, 12:27 PM

Make sure you have enough height clearance for the taller tires. Dexter Axles recommends a minimum "bump clearance" of 3".

FastEagle

Civilian Campgrounds & RV Parks

SmokeyWren · 05-09-2012, 04:50 PM

Wheels will be your problem. I haven't found 16x6" wheels with 5 on 5.5" bolt pattern. There are very few available with 6 on 5.5" bolt pattern. Almost all have either 6 on 6.5" or 8 on 6.5".

If you can't find 16" wheels to fit your hubs, then that means you'll have to replace the hubs with some that have 6 on 6.5" bolt pattern. Then you must match hubs to brakes. Maybe have to replace brakes too. Good luck. It's probably simpler and maybe less expensive to just replace the entire axle assemblies with new ones that have 6 on 6.5" bolt pattern.

A lot less expensive would be to replace your 225/75R15D tires with 225/75R15E. Maxxis makes them. Discount Tire sells Maxxis trailer tires.
Get Maxxis 225/75-15 Tires in the Midland Area at Discount Tire - Discount Tire/America's Tire

If you do that, when you dismount the old tires from the wheels, check the inside of the wheels for the max PSI and/or max weight they can handle. If it's less than what the new tires can hold, then you'll need new wheels too.

I had a similar problem with my previous RV trailer. It came with 205/75R15C on 5.5" wide rims, and they blew out bang, bang, bang. So I replaced them with 225/75R15D on 6" rims, then never had more trailer tire problems.

Since then I've replaced the tire/wheels on two other trailers that had 205/75R15C with 225/75R15E. No more trailer tire problems on those trailers either.

I'm facing the same problem with my new RV trailer, except it's a much lighter trailer with 14" tires. I'll probably replace them with 15" Maxxis after a 4,000 mile trip near the end of this month. If I get home with all 5 of the standard tires, then maybe I won't replace them. But I suspect that won't happen.

Ray,IN · 05-09-2012, 08:52 PM

The minimum clearance between tandem tires is 1.5", any closer and they can rub when they become hot and expand at highway speeds. This information is from the truck tire shop that moved my rear tandem axle to accommodate larger tires.

SmokeyWren · 05-10-2012, 07:28 AM

Quote:

Originally Posted by SmokeyWren

A lot less expensive would be to replace your 225/75R15D tires with 225/75R15E. Maxxis makes them. Discount Tire sells Maxxis trailer tires.
Get Maxxis 225/75-15 Tires in the Midland Area at Discount Tire - Discount Tire/America's Tire

Note that unlike most trailer tires, those are NOT speed-limited to only 65 MPH. They have speed simbol "R", which is 112 MPH. So with those tires you can keep up with traffic on west Texas interstates with speed limits of 75 and 80 MPH.

Quote:

Originally Posted by Ray

The minimum clearance between tandem tires is 1.5", any closer and they can rub when they become hot and expand at highway speeds.

According to the tire calculator on the Maxxis website, 235/85R16 tires - such as the outstanding Michelin XPS Rib - are 3.44 inches more diameter than 225/75R15. So the space between the tires on a tandam axle trailer would be reduced by 3.44". My new RV trailer has only 3" clearance between the stock tires, so I could not install tires that have 3.44" additional diameter without moving an axle.

Also, your trailer may have limited clearance between the top of the tire and the bottom of the fender well. When I upgraded the tires on my 5er from 205/75R15C to 225/75R15D the tires would rub the fender well when I hit a sharp bump. No harm done but I could tell that the fender well had been banged on, and the tires were scuffed where the contact with the fender well was made. So even if your tandam axles are spread apart so clearance between tires is no problem, you may have to lift the trailer to get more clearance in the wheelwell.

gundog · 05-10-2012, 10:29 AM

My current 15" rims are 6 lug so hopefully the 16" rims will be the same pattern. My 225s are 28" tall and the 235s are 31". Currently the distance between the front axle tire and the rear is 5" and 4" from the top of the 225s to the undercarrage. Trailer is still in the shop. Correct my if I am wrong assuming the bolt pattern matches. I should be deviding the differencein hals which would meen I would loose an inch and a half of clearence between the front and rear tire as well as from the top of the tire to the frame. Is this right and will it work.

The reason I did not go with LT tires was I just read to many opinions, some say they are much better some say the sidewall are alot weaker. But most recommended the 235 maxis.

SmokeyWren · 05-10-2012, 03:59 PM

Quote:

Originally Posted by gundog

My current 15" rims are 6 lug so hopefully the 16" rims will be the same pattern.

They probably will. Most 16" trailer wheels have 6 on 6.5" hole pattern, but some have 6 on 5.5". You need to know which you have before you order wheels.

Quote:

Correct my if I am wrong assuming the bolt pattern matches. I should be deviding the differencein hals which would meen I would loose an inch and a half of clearence between the front and rear tire as well as from the top of the tire to the frame. Is this right and will it work.

You're on the right track, but not exactly right. Your tires will be an inch and a half closer to the wheel wells. But each tire will be an inch and a half closer to the other tire, so the distance between the tires will decrease by the full 3".

gundog · 05-10-2012, 07:06 PM

DUH! Thanks SmokeyWren. That still gives 2 inches.

gundog · 05-14-2012, 06:22 PM

Well, they did not fit. Was close but only had about an inch left for clearance so went back and exchanged them for 225 75r 16e LT BF Goodrich commercial tires. Much heavier then the 225 75r 15T that were the OEM tires. hope I made the right choice.