2004 Class C Coachmen Leprechaun 317 KS Tires

[RANGERZ21]

Looking for advice on new tires for my 2004 Class C MH. LT225/75R16 load range E. I have out dated Mich's on it now.(which look brand new) I am not a full timer so I am not looking to drop a ton of money in a set of tires that will be replaced due to age as opposed to being worn out.
Thanks in advance

 

[Molaker]

When I bought my class C Coachmen in 2009, it had 6 relatively new Cooper LT tires on it (dated 2007).  The OP had upped the size from LT225/75R16-E to LT235/85R16-E.  The front-end had a problem and wore the two front tires a bit oddly so when I had the front-end repaired, I replaced the front tires with two more Cooper tires (dated 2010).  I only paid about $125 ea. and have run about 12,000 miles since - with no problem except for a faulty valve stem.  I don't futz with tire pressure.  I run my tires at the pressures recommended (inside driver's door) and I don't typically load the MH very heavily.  Also, I don't drive very fast (60-65 max, usually less).

As for your "outdated" tires, just how outdated?  How many miles on them and how often have you driven your MH?

 

[RANGERZ21]

I just purchased the RV. I have not taken it out yet. The Mich that are on it now are so cracked that I'm surprised they are holding air. They are probably the original tires since the MH only has 7700 miles on it. Here are some specs on going to a differant size

225/75/16                                                                235/85/16
Diameter inches (mm) 29.29 (743.9)            31.73 (805.9) 2.44 (62) 8.3%
Width inches (mm) 8.86 (225)                        9.25 (235) 0.39 (10) 4.4%
Circum. inches (mm) 92.01 (2337.03)            99.68 (2531.81) 7.67 (194.78) 8.3%
Sidewall Height inches (mm) 6.64 (168.75)    7.86 (199.75) 1.22 (31) 18.4%
Revolutions per mile (km) 688.63 (427.64)    635.65 (394.74) -52.98 (-32.9) -7.7%
As you can see the 235 is a much taller tire. A taller tire takes more force (aka horse power) to rotate. Also the speedometer

Speedo Reading          Actual Speed
20 mph (32.21 km/h)    21.67 mph (34.89 km/h)
25 mph (40.26 km/h)    27.08 mph (43.61 km/h)
30 mph (48.31 km/h)    32.5 mph (52.34 km/h)
35 mph (56.36 km/h)    37.92 mph (61.06 km/h)
40 mph (64.41 km/h)    43.33 mph (69.78 km/h)
45 mph (72.46 km/h)    48.75 mph (78.5 km/h)
50 mph (80.52 km/h)    54.17 mph (87.23 km/h)
55 mph (88.57 km/h)    59.58 mph (95.95 km/h)
60 mph (96.62 km/h)    65 mph (104.67 km/h)
65 mph (104.67 km/h)  70.42 mph (113.39 km/h)
As you can see at 65 you are really going 70.42 mph

 

[Gary RV_Wizard]

It's not the '235' that made it a lot taller - it's that '85' aspect ratio that threw things off. Find a 235/75 or even a 245/75 and the numbers will be very close. For example, a General Tire LT245/75R16 turns 681 revs/mile and has little effect on the speedo or anything else.

The 245/75 size is much more common than 235, so you would have more choice. Just make sure the front wheel wells have room for a bit wider tires -  20 mm is about 3/4".


However, it hasn't been established that bigger tires would be beneficial. If the tire load rating on the OEM tires has plenty of extra carrying capacity vs the axle loads, then you may as well stick with the 225's.  Check your axle weight ratings vs the tire's own load carrying capacity (embossed on the sidewall) to see where you stand.

 

[Molaker]

I was not recommending you change your tire size, only explaining what my MH has.  Mainly, I wanted to relay my experience with the lower priced Cooper tires.

FWIW - The larger tires haven't seemed to have any noticeable impact other than throwing off the speedo by about 10%, so I use my GPS for a speedo.  The PO had these larger tires put on because he had a couple of blow-outs on a trip out west and decided to replace the entire set.  The LT235/85 was all that was available where he was.  Other than the speedo issue, I'm quite satisfied with the tires.