Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×
 
 


Reply
 
Thread Tools Display Modes
 
Old 06-24-2015, 12:57 PM   #1
Gold Member
 
mass59k's Avatar
 
Join Date: May 2015
Location: MASSACHUSETTS
Posts: 86
Send a message via Yahoo to mass59k
Default Promaster tire pressures

Have rec's changed about tire pressures? I seem to remember Motor Home tech advised 5 pounds over what was on tire. Our tires are not LT rated..they are truck/commercial. My 59k tires say 80 pounds cold..I'm running high 70's front and back. Noticed Winnebago wants 65 front and 72? rear. Questions:
1. Is the lower pressure in front because of front wheel drive?
2. IF I adhered to WB's pressures would I be totally safe regarding all weights in the camper. We travel with 1/3 water and now a spare off receiver hitch AND 2 bikes sometimes.
What do you all think? ???
Wayne in Mass 59k
__________________
Wayne from Mass
2016 WGO Travato 59k
mass59k is offline   Reply With Quote
Old 06-24-2015, 01:10 PM   #2
Platinum Member
 
wincrasher's Avatar
 
Join Date: May 2014
Location: Greer, South Carolina
Posts: 2,611
Default

Follow the sticker in the door jamb. It calls for a lower pressure on the front wheels than in the back.

If I remember correctly it's 65 psi up front, 72 psi on the rears.
__________________
2019 Winnebago Travato GL
Follow my blog: https://www.wincrasher.blogspot.com
Our Facebook group is: https://www.facebook.com/groups/ClassBCamperVans/
wincrasher is offline   Reply With Quote
Old 06-24-2015, 01:44 PM   #3
Platinum Member
 
Join Date: Aug 2010
Location: Minnesota
Posts: 11,917
Default

Optimum tire pressure setting is a very interesting project, that can really give some surprisingly good improvements in handling on some vehicles. It can also be dangerous if you do it wrong, to the low pressure side in particular.

From what I have found (not official) the door post stickers are based on what load those tires could see at their maximum load, which would be axle load for single wheels. It may, or may not, have anything to do with reality in a final vehicle like a B. For example, a Roadtrek 190 on a Chevy has a rear axle rating that is right at the tire rating maximum, so the sticker gives a tire pressure of 80psi, which is the max tire pressure (where it will carry the highest load). The front axle rating is only about 70% of the tire rating, so they put 50psi on the sticker, based on a tire manufacturer load chart I think.

If you are under the axle ratings, you could theoretically lower the tire pressures by some, based on the tire load capacity charts. Many folks, me included, have found that going as low as the charts say can make the vans handle poorly. It is more common for folks to go above the sticker recommendations, if the tire isn't already at max, to try to improve handling. All the Chevy, Ford, and Dodges seem to react well to higher front tire pressures.

There was a pretty good discussion on tire pressure tweaking on the board a while ago.

http://classbforum.com/forums/showth...ght=roadmaster

The front drive Promaster will be slightly different in reactions, but all the same principals apply.

From what I have seen in front driver cars I would generalize:

Front drivers tend to understeer more in most cases, and it will get worse when accelerating or decelerating without using the brakes.

Most front drive, strut suspension, setups have negative scrub radius, so when a tire hits a puddle or big bump it will try to turn in toward the center of the vehicle instead of out like rear drivers normally do. This usually makes them much less likely to move around as much when you hit things like puddles.

Torque steer can be noticeable or not depending on the vehicle.

The attached thread explains it pretty well, but it will be interesting to see what folks come up with on Promasters to get the best handling.
booster is online now   Reply With Quote
Reply

Thread Tools
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

Powered by vBadvanced CMPS v3.2.3

All times are GMT. The time now is 07:05 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2024, vBulletin Solutions, Inc.