Thread Tools Search this Thread Display Modes
Old 09-08-2012, 08:17 AM   #1
CapriRacer's Avatar
I'm in the , US
Join Date: Sep 2012
Posts: 659
7.00-15LT vs P235/75R15 XL

Top asked me to join in on conversations about 7.00-15LT’s – particularly with regard to replacing those with P235/75R15 XL’s. The threads he pointed me to were cluttered with other topics – so I decided to start a new one.
Diameter: 29.6”
Width: 8.0” (on a 5.5” rim)
Load Carrying Capacity : Load Range C: 1710# @ 45 psi (bias) / 50 psi (radial) – Single (I am not going to quote duals)
Load Range D: 2040# @ 60/65
Load Range E: 2335# @ 75/80
Speed restriction: 65 mph

P235/75R15 XL
Diameter: 28.9”
Width: 8.8” on a 6” rim (8.6” on a 5.5”)
Load carrying capacity: 2183# @ 41 psi (1985# @ 41 psi when used on a trailer)
Speed Restriction: Varies by tire

My first reaction is that it is smaller in diameter, wider (a concern!), and for Load Range C - on paper - there is enough load carrying capacity. For Load Range D – on paper – there is a difference of 55# (the wrong way) - and here is where it gets complex.

Because of the difference in speed restriction, this weight difference is not a concern - FOR ME!!. It may be a concern for others – and that is understandable.

Taking this a next step – Load Range E: On paper, there is a 350# difference – and I think this is just beyond the limit (adjusting for speed)

Let’s look at an ST tire:

8.0 on a 5.5” rim
Load Carrying Capacity: Load Range B: 1480# @ 35 psi
Load Range C: 1820# @ 50 psi
Load Range D: 2150# @ 65 psi
Aside from the load carrying capacity and the reduction in diameter, this appears to be a viable option.

How about ST225/75R15?
8.8” on a 6” rim (8.6” on a 5.5” rim)
LR B: 1760# @ 35 psi
LR C: 2150# @ 50 psi
LR D: 2540# @ 65 psi
Aside from the width, this looks viable.

I want to take a moment to talk about clearances:
First, I am not a fan of tires contacting body parts, frames, and suspension members. Bad things have been known to happen.
Diameter: That’s pretty easy to deal with. The static clearance can easily be measured and there is an obvious limit before the suspension bottoms out.
Width; The static clearance can be measured, but under cornering, the issue becomes less clear. I am VERY nervous about width clearances, so I tend to emphasize staying close to the original dimension.
And those are my thoughts.

CapriRacer is offline   Reply With Quote
Old 09-08-2012, 11:03 AM   #2
Always learning
Top's Avatar
1972 29' Ambassador
1962 19' Globetrotter
1951 21' Flying Cloud
Central , Texas
Join Date: Oct 2010
Posts: 2,779
Images: 24
Blog Entries: 2
Send a message via Yahoo to Top
Thanks very much for your thoughts and numbers.
So as long as there are no clearance issues, you would recommend these P235/75/15XL to replace original equipment 7.00x15LT bias ply load range C or D?

Work is never done, so take time to play!
Top is offline   Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Featured Campgrounds

Reviews provided by

Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 10:03 PM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.

Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.