Tire pressure help

[tiredvet]

This coming week we will pick up our 2003 34FDDS. It has new Bridgestones 295/75R 22.5 G's on. My question is what air pressure to run up front and back. The coach will be at it's empty weight (unpacked). The trip home will be 1200 miles and I want to be sure that I have a comfortable ride home. I did a search but could not find anything on this exact tire. Bridgestone says 110 psi.

[Midniteoyl]

Do you happen to know the actual weights?
Only way to be sure..

You could take the OEM's Empty weights, front and rear, add for any fuel and people, then divide by the number of tires on the axle, match that number to the load charts and add 10 psi to be sure..

http://www.trucktires.com/bridgeston...loadTables.pdf

[Bigbluedog55]

tiredvet,

For tire inflation go to the tire manufactures web site, find your tire and see what the inflation for load is...you must weigh your coach and get, at a minimun, the front and rear axle weights. Inflate the tires to carry that amount of weight.
The only way to know the correct inflation pressure is to weigh the coach when it is packed and ready to travel.

Luck,
Bob

[Old Scout]

According to the Bridgestone website the 295 75R "G" has a max air pressure of 110 PSI. At that level, you can carry 6175lbs on a single tire [max axle 12,350lbs] on the front and 5675lbs per dual tire [max axle 22,700] on the rear. So at 110 lbs in front and 95lbs rear [5070lbs on each dual tire [20,280lbs axle]] in rear will get you home just fine--then you can weight you coach later. Opinions vary on this but with our coaches, 12-13k axle in front and 20,000 rear axle, many owners have opted for load range "H" tires to give them a greater margin of safety on the front axle.

[tiredvet]

Looking at the 2003 brochure the peak chassis weight is distributed 60/40. The unloaded vehicle weight with fuel is 23450. If I fill the fresh water half way say 50 gallons that's another 425 lbs and say a 100 lbs of luggage brings total weight to say 24000 lbs. 60% is 14400 lbs rear leaving 9600lbs front add in 350 lbs for we two for a total of 9950. Checking these weights on the load table for this tire +10 lbs is 90-95 lbs front and 85 lbs in the rear. Does this sound correct or close. I truly understand that by actual known weight of each axle is the true way to properly inflate the tires according to the load chart. Old Scout thanks for the info. There's not a lot that I am going to be bringing with me to go and pick up our coach and what I need to know is a good guess as to how much pressure to use. My math may be wrong but I was trying to make a determination based on the weights and measures info from the brochure. Please feel free to show me where I'm going wrong with using 85 lbs in the rear and 95 lbs up front.

[mythplaced]

40MDTS....

Fully loaded with fuel and water and access..

105 front
95 rear

Ride is good

[Old Scout]

Cant argue your calculations--if the load charts say you can do it, I guess you can do it. If you do go with estimated weight, recommend 10-15% increase. Road slant, wind speed/direction and aggressive maneuvers can all transfer weight from one corner to another or from back to front. You cant exceed 110 PSI with your particular tires, but you can under-inflate them and under-inflation can definitely harm/ruin a tire. Empty weights vary by length of coach--so owners of shorter coaches can go with more carrying capacity or less tire pressure. Comparing with other owner, I rarely hear of folks running below 100 in front and 90 in the rear but I am sure some do. I am incline to "error" on the side of caution. Safe travels......

[Midniteoyl]

Do 100/90 psi... Best bet and keeps you safe.

[toneumanns]

Originally Posted by Midniteoyl

Do 100/90 psi... Best bet and keeps you safe.

I used to do that but then I weighed my coach & downloaded Michelins tire pressure guide. Per their instructions I lowered my pressure according to weight on each axile which resulted in a much better ride & handling.

[Midniteoyl]

Originally Posted by toneumanns

I used to do that but then I weighed my coach & downloaded Michelins tire pressure guide. Per their instructions I lowered my pressure according to weight on each axile which resulted in a much better ride & handling.

But, he do not have the weights.. thats the whole point.

[toneumanns]

Originally Posted by Midniteoyl

But, he do not have the weights.. thats the whole point.

Well then go weigh it instead of using generic tire pressures! That was my point.

[OldForester]

I have 295/80 Bridgestones on mine, and our 36' weights 29,500 fully loaded. I run 100 to 105 in the front and 90 to 95 in the rear and have plenty of safety margin and a nice ride.

But the G rated size you have may command a different pressure. I have a Bridgestone tire data book for truck tires in pdf form that I can e-mail you if you PM me with your e mail address.

[Algoma]

I don't know why people who do not have an Alpine Coach feel they have to put their spoke in. The answer is that the manufacturer's recommended pressures for a fully loaded coach are listed on the VIN plate located on the forward face of the bulkhead. When your coach is configured how you normally use it you should get it weighed and then you can reduce the pressure if your axle weights are below the maximum ratings. The Bridgestone website has a tire loading chart that you can use to determine the correct pressure. The H or G rating does not affect the tire pressure only the maximum load that the tire can handle.
FYI. The plate on my coach says 95psi front and 95psi rear. I run 95 front and 85 rear.

[tiredvet]

Thanks for all the advice every one. I am going to go with 100 lbs front and 90 lbs in the rear. I will get more specific with the air pressure after I get back and load some items. Then I will get the coach weighed and adjust the tire pressure.Thanks for the offer Old Forester but I have down loaded the load data from Bridgestone already. If my coach was any bigger or it had any extra load I would run 105/95. Thanks again everyone, after We get back this Saturday I'll post a photo and add our coach to the Alpine Registry. Jim & Elissa Edmonds (not the ball player,I had the name first).