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Topic: Tire Inflation (Read 1251 times) previous topic - next topic

Re: Tire Inflation

Reply #25 –
Quote from: dans96u295ft –
This is my 6th RV in 25 years and never had a blowout running max or 10 psi less than max on the RV's or trailers.

OK, that could mean that your previous RV's speced tires that had less safety reserve and did require at or close to full PSI to support their actual weight. Don't know without facts on both tires and weights.

That COULD be true with your Foretravel, but without 4 wheel position weights (best) or at least axle weights, all of us (and you) are having to express an opinion rather than base PSI on FACTS.

BTW, excellent plan to contact Uniroyal and have them e-mail you or give you a link to the inflation table for your tires.  They spent a lot of $$ and research to develop the table.  Take advantage of it.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Tire Inflation

Reply #26 –
Quote from: dans96u295ft –
I weighed my coach without water or groceries, etc etc. True empty except cargo area full. 27,500 total. I did not weigh axles separate yet. I'll play with 100 to 110 when loaded and weigh it again. This has been my winter project and only drove it over the winter on nice days and empty. I also pull a 20 foot cargo trailer weighing in at 4500lbs.
Thanks for the info. I'll call Uniroyal direct.....

90 lbs all the way around, by the attached Uniroyal tire inflation guide takes you to the 30,000 GVWR of your rv.  That is 10,500 front, 19,500 rear.

From my earlier post: "As an example, to compare mine to yours, I load my rv heavy, near the axle limits rated by the FT plate at 10,500 front 19,500 rear.  So off the Toyo chart, I use 105 in the front, 90 in the rear.  This gives me a tire capacity of 10,740 in the front, 19,540 for the rear duals.  Using the Uniroyal chart for your RS20 275x80x22.5, 90 lbs all the way around would give you 10,740 front capacity and 19,540 rear capacity respectively........"
97 U295 40, Build #5040, 6C8.3 325 HP
Oregon Continuous Traveler
Samsung Residential #RF20HFENBSR,
Xantrex SW2012, (3)AGM8D Hse, (2)AGM Grp24 Eng, Victron BMV-712, 1800w Solar 4 LG & 2 Sunpower
Extreme Full Body Pt w/hdlmps, new furn/floor, 4 down Lexus 2004 GX470 AWD curb weight 4,740 lbs
Prev: 1990 Barth, 10L 300 2 yrs; 91&92 Monaco Signature, 10 yrs, 10L C 300 &  6C8.3 300; 1997 ForeT 6C8.3 325 since May 2017.  Employed by Guaranty RV 14+ yrs.  Former VW New Car Dlr/Service Dlr, Sales Mgr, Rv Sales, and Service Adviser from 1968-2017
"Don't criticize what you can't understand" Bob Dylan

Re: Tire Inflation

Reply #27 –
Our bad roads here in so cal required the highest capacity tires made so we could lower the correct pressure per the load to have the best possible ride quality.  Then add the Koni fsd's

Fixed. 

If you have good roads then you can skip most of this as the differences may not be apparent until you hit bad roads.

Just saying.  We had a need that had to be addressed,  you may not.
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: Tire Inflation

Reply #28 –
Ok. Called Uniroyal-Michelin and they want fully loaded corner weights on all 4 to determine psi as some have stated. They recommend if you don't know it, max to 120 psi to be on the safe side. When I get it fully loaded and ready to use, I'll call them back with corner weights and report back at their recommendations
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.
 

Re: Tire Inflation

Reply #29 –
Quote from: dans96u295ft –
Ok. Called Uniroyal-Michelin and they want fully loaded corner weights on all 4 to determine psi as some have stated. They recommend if you don't know it, max to 120 psi to be on the safe side. When I get it fully loaded and ready to use, I'll call them back with corner weights and report back at their recommendations

Until you can load and weigh, just take the maximum weight rating of the axles and either call them or use the following pdf file. That would be the GVWR (Gross Vehicle Weight Rating) axle ratings that are on your federal FT weight sticker by the drivers seat.  Might be 10,500 up front and 19,500 on rear axle till you can weigh. So corners would be 5,250 lbs up front and 9,750 lbs on duals in the rear.

Off the following Uniroyal data book for your RS20's, 275x80x22.5, that would be 90 lbs all around to carry 10,740 on the front axle and 19,540 on the rear axle.

If you believe the rv is not loaded evenly, add 5-10 lbs to each tire, until you can load and weigh properly.
97 U295 40, Build #5040, 6C8.3 325 HP
Oregon Continuous Traveler
Samsung Residential #RF20HFENBSR,
Xantrex SW2012, (3)AGM8D Hse, (2)AGM Grp24 Eng, Victron BMV-712, 1800w Solar 4 LG & 2 Sunpower
Extreme Full Body Pt w/hdlmps, new furn/floor, 4 down Lexus 2004 GX470 AWD curb weight 4,740 lbs
Prev: 1990 Barth, 10L 300 2 yrs; 91&92 Monaco Signature, 10 yrs, 10L C 300 &  6C8.3 300; 1997 ForeT 6C8.3 325 since May 2017.  Employed by Guaranty RV 14+ yrs.  Former VW New Car Dlr/Service Dlr, Sales Mgr, Rv Sales, and Service Adviser from 1968-2017
"Don't criticize what you can't understand" Bob Dylan