LT tire upgrade Cougar 327RES

Go to the tire mfg web site, look up the specs for the brand you want to buy and compare diameters. Diameter does vary by manufacturer so there can be no general answer.

For LT235/85R16E's you need 33" inches or more center to center on your axles! Plus clearance above the tires. Chris

When I changed my ST235/80R16's to LT's I went with 245/75R16's. They have a slightly wider tread but the diameter stayed the same.

I see the '12 Keystone Cougar 327 RES shows a 11945 GVWR which may mean a 5.2k axle rating on the trailer.

The ST235/80-16 E tires are 30.7" diameter.
Many folks replace them with a LT245/75-16 R that has a 30.4" diameter.

The LT245 E tire has a wider section width so measure close. LT tires on my 11200 lb trailer have 1" between the tires and 2 3/4" clearance at the top and 3/8" on the inside next to the shock.

You stand to lose almost #400 per tire. Can you do that?If you can, then proceed to the Manufactuers data sheet as to physical dimentions

I have a 04 Keystone Challenger that came with Tacoma LT 235-85-16 tires on it.
They were putting LT tires on trailers back then. My sticker on the side of trailer even shows LT 235-85-16. I have a GVW of 14000 lb. with 6000 lb. axles. I don't see you having a problem with them as long as you have the upper clearance. I could only put 2 fingers between my tires and never had a issue. I just recently put on Michelin MS/2 tires on beginning of last year and they have worked out great. wear is perfect and no issues with them.

aruba5er wrote:
You stand to lose almost #400 per tire. Can you do that?If you can, then proceed to the Manufacturers data sheet as to physical dimentions

I hadn't even looked up the specs on that size yet, however great point. And, no probably would not want to do that.

That was a good suggestion going with the 247/75's. The recommended rim diameter is 1/2" more though, 6.5" vs 6.0". Cooper makes a fine LT tire for trailer purpose. I'm currently running SRM II's and the are a commercial ribbed tire. Supposedly the SRM's are no longer being made, but you can find them if you try or go to a suitable Cooper replacement. Do a search, it's on here.

rattleNsmoke wrote:
That was a good suggestion going with the 247/75's. The recommended rim diameter is 1/2" more though, 6.5" vs 6.0". Cooper makes a fine LT tire for trailer purpose. I'm currently running SRM II's and the are a commercial ribbed tire. Supposedly the SRM's are no longer being made, but you can find them if you try or go to a suitable Cooper replacement. Do a search, it's on here.

Most here that recommend Coopers use the Discoverer HT3. I plan to get these in a few weeks just before we go to Myrtle Beach as our current ones are greater than 3 years old.

MO_Trout_Bum wrote:

aruba5er wrote:
You stand to lose almost #400 per tire. Can you do that?If you can, then proceed to the Manufacturers data sheet as to physical dimentions

I hadn't even looked up the specs on that size yet, however great point. And, no probably would not want to do that.

While it is true that the LT tires are rated about 400 lbs less, in my opinion, they are still superior. LT tires that are comparable in size to the ST tires will have a 3042 lb load rating which is just fine for both 5.2K and 6K axles. You most likely have 5.2K axles. So the LT tires will have a load rating that is higher than the axle rating anyway, so the higher rating for the ST tires is irrelevant.

I switched from ST to LT when my fiver was just a yr old.