Coach Weight

[Dick Simonis]

When I got my new Hankook tires yesterday I also got an alignment and had it weighed.

With 1/2 tank of fuel and 1/4 tank of FW it came in at:

Front:   10760
Rear:    20280
Total:   30940

According to the manual the empty weight was ~32,00 and the GVWR is 36,000.

We normally travel with 1/4 to 1/3 FW but if the fuel tank was full it would add ~350 lbs more to the front and total.

We're pretty much loaded with our normal traveling stuff but even so the bays are not even close to full and, according to the tire inflation guide I should run between 100 and 105 psig in all tires.  It's interesting that all the tires have pretty much the same weight on them .

I curious if anyone with a similar coach to our 2 slide 2000 PT have had theirs weighed and how the numbers look.

[Joel Weiss]

We have a 2000 Patriot Thunder 2-slide Princeton and consistently run higher weight than you are showing.  With a full tank of fuel and half tank of water we're running ~11,400 on the front and ~21,500 on the rear, for a total weight of ~32,900.  The coach is rated at 13,200, 19,500, and 32,700 respectively.  You have confused the GVWR of 32,700 with the GCVWR of 37,700.  You can verify these on the "plaque" that should be affixed on the wall behind and to the left of the driver's seat.

I'm surprised that you are so much lighter than we are; our weights are consistent with weighings done by the previous owner.  Our weights include two passengers (~400 lbs) in case yours didn't.  We are full-timers so we probably have more stuff than you do, but it's hard to imagine taking 1,000 pounds out of here.  (BTW your total appears to be 31,040, so with fuel and two people you could be up to ~31,800.)

When I got new Michelins this summer, I discussed the weight issue with the owner of the facility who seemed pretty knowledgeable.  Since the Michelins are Load Range J there is no issue with them being able to handle the load.  He said that the axles ratings typically have at least a 10% safety factor and that my rear axle and tire wear patterns did not show any indication of overloading.

Based on the axle weights he calculated tire pressures of 98 for the rear and 108 for the front.  Although all your tires may have the same load, it is important that you use the inflation chart for the tires when used as duals and not as singles.

I'd like to know what model Thunder you have.  I suspect that the large slide in the Princeton may account for some of the difference in weight.  

Joel

[Jerry Carr]

Hi Dick,
We had our 06 weight done at the FMCA we came in @ Rt FT 6950-Rt Drive 10050 Rt Tag 4140  total Rt. side 21150
the Drivers side was FT 6950 Drive 8650 and tag 4550 total drivers side 20150

We are in good shape with full tanks Under Weight on all wheels front 1260lbs ,Drivers 4300lbs and the tags 1300lbs.
The only issue we had was 1400lbs out from left side to right side I really don't see a cure for this issue.

The book tells us to run 115lbs on the fronts and 85lbs on all the rear tires, ( I am now running 110lbs(cold) on the fronts this will move to 121/124 on the fronts after about 2 hours  the rears I choose to run 90lbs (cold) these run at about 100/103.

I was not able to find the GCWR weight tag??

I feel much better now with the real weights /tire pressure, the Tire Sfe Guard system can now do a much better job.

[Joel Weiss]

Hi Dick,
We had our 06 weight done at the FMCA we came in @ Rt FT 6950-Rt Drive 10050 Rt Tag 4140  total Rt. side 21150
the Drivers side was FT 6950 Drive 8650 and tag 4550 total drivers side 20150

You are nearly 1500 lbs heavier on the right side of your driving axle compared with the left.  I assume you know that your tire pressures on that axle should be high enough to cover the load on the heavier side; both sides must have the same pressure.  

Since you have exact weights there's no reason to use the coach manufacturer's general tire pressure recommendations.  Your tire manufacturer will have a website with the appropriate inflation information as a function of load.  There will be columns for when the tires are used as singles and when they are used as duals.  The load ratings are significantly different and you must use the correct ones.  The tires should be fully filled to the cold pressures; the increase in pressure during driving is "built in" to the tables.

If you happen to have Michelins on the coach the load ratings for all Michelin models can be found here:  http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=4&sqi=2&ved=0CHQQFjAD&url=http%3A%2F%2Fwww.michelinrvtires.com%2Fassets%2Fpdf%2FRVTiresBrochure.pdf&ei=0jokT6jPH9CEsAL_u-CMAg&usg=AFQjCNGTNAmUZadaZ8wT

Joel Weiss

[Dick Simonis]

We have a 2000 Patriot Thunder 2-slide Princeton and consistently run higher weight than you are showing.  With a full tank of fuel and half tank of water we're running ~11,400 on the front and ~21,500 on the rear, for a total weight of ~32,900.  The coach is rated at 13,200, 19,500, and 32,700 respectively.  You have confused the GVWR of 32,700 with the GCVWR of 37,700.  You can verify these on the "plaque" that should be affixed on the wall behind and to the left of the driver's seat.

I'm surprised that you are so much lighter than we are; our weights are consistent with weighings done by the previous owner.  Our weights include two passengers (~400 lbs) in case yours didn't.  We are full-timers so we probably have more stuff than you do, but it's hard to imagine taking 1,000 pounds out of here.  (BTW your total appears to be 31,040, so with fuel and two people you could be up to ~31,800.)

When I got new Michelins this summer, I discussed the weight issue with the owner of the facility who seemed pretty knowledgeable.  Since the Michelins are Load Range J there is no issue with them being able to handle the load.  He said that the axles ratings typically have at least a 10% safety factor and that my rear axle and tire wear patterns did not show any indication of overloading.

Based on the axle weights he calculated tire pressures of 98 for the rear and 108 for the front.  Although all your tires may have the same load, it is important that you use the inflation chart for the tires when used as duals and not as singles.

I'd like to know what model Thunder you have.  I suspect that the large slide in the Princeton may account for some of the difference in weight.  

Joel

Joel, I have the same model as yours.

If I add in a bit for more fuel and put us in the coach we will be real close to what you are running.  A 180 lb guy took it over to the scale.

I can't quibble over a few pounds one way or the other but figuring the scales are probably +/- 1% or so.  It looks like we agree within acceptable measurement error.

We weren't quite loaded to full travel wt for this trip.  Lacking about 200 lbs of liquor and another 100 of food...but still it's interesting that we, like you, are also over the RAWR.

Using the Hankook inflation chart I would run ~100 psig front and rear but I'll probably go for 110 all around....over is much better than under.  Interestingly, around here right now the temp change alone from early morning to mid day moves the tire pressures 5-6 psig without the coach even moving.  Oh well, I need something to obsess about.

Like yours, my 10 yo Toyos in the rear were about perfect for wear pattern even though the axle was 1/8" out. Fronts weren't so good as there was significant tow in.

The combination of tires and alignment has done wonders for the ride and handling.

[Gil_Johnson]

Dick and Joel,

You are overloading your drive axle.  If you can, find a way to move weight forward.

[Gil_Johnson]

Jerry,

If the required pressure is 115psi, then that's what you should be inflating the tires to when cold and nothing less.  The pressure when hot can tell you a few things, like defective brakes, but hot pressure can't indicate correct tire pressure.

[Joel Weiss]

Much easier said than done; apparently this is a consequence of the massive C-12 in the rear.  As I noted, my tire dealer did not see any evidence of the axle flexing under load.  He felt we were probably within the safety margin; not much more we can do.

[Dick Simonis]

To do that I'd have to take out all our clothes, the washer/dryer, and the refirg.  Like Joel said, can do much about it and my best guess it that we'd be at the max axle loading if the coach was completly empty.  I'll bet I don't have 1,000 lbs of stuff on board total.

[Gil_Johnson]

Axle weights seem to be an issue with many coaches, regardless of brand.  I bought a tag axle coach specifically to overcome the drive axle weight concerns I've heard from many.  Most others far more over loaded than yours.  What I didn't expect to find is that my front axle is not far from overweight.  At the end of the day, shame on these coach manufacturers for not doing better weight planning for real world use.  There's no reason to put the fuel and water tank right behind the front axle of a coach with a tag axle.  For you that have that have that monster engine, fuel and water up front would probably make sense.

With a full tank of fuel and less than a half a tank of water here's my weights:
Front axle 13500
Drive Axle 15600
Tag Axle    7920

Although the tag axle is adjustable and Monaco recommends 10,000 on the tag, most reduce the weight on the tag to reduce the weight on the front axle.

Your know having a C-12, you might want to consider a tag axle to serve as a wheelie bar.  With all that power your front tires probably come of the road when leaving from a traffic light.  Just couldn't resist.

[Joel Weiss]

But I just love laying rubber as I move out from a light!   We're thinking of entering the beast in some drag races while we're down south!  

[Richard And Babs Ames]

Joel do you use a "line lock" like drag racers use?

[Phil N Barb Rodriguez]

I had a line-lok on my '69 SuperBee race car  

For info: We had our coach weighed in Jan. '07 at the FMCA Indio, Ca rally. The Recreation Vehicle Safety Education Foundation (RVSEF) weighed each corner. The numbers:

            Left   +   Right=   Axle Load
Front:   5600  +   5500=   11,100                        Front GAWR= 13,200
Rear:   10,400 +  10,200= 20,600                       Rear GAWR = 19,500

Total Axle Load= 31,700                                     GVWR  =  32,700

My wife and I were both aboard during weighing.

Note that the black tank was ~50% or roughly  210 lbs
The grey tank was ~70% or roughly   330 lbs

The fuel tank was at 1/2 or ~60 gals  385 lbs
The propane  tank was at 70%           150 lbs
The water tank was 25% full               160 lbs

I rarely travel with anything but a "charge" in my holding tanks, so lets take that 540 lbs off the rear axle.
I usually travel with 1/2 tank of water, so let's add 160 lbs to the front.
And then there is the fuel. A full tank would add another 300 + lbs to the front axle. But that doesn't last very long so let's leave that alone.

So I could say that the rear axle is overloaded by 540 lbs, Don't know if the ~30 ft span from axle to axle with the additional weight added to the front would take more weight off the rear axle.

Although we liived in our coach 5 days a week in Seal Beach, Ca. it is NOT configured for full time. It's pretty loaded but not with all the extra "stuff" we would have aboard if we were true full timers.  
  
Hope this helps those with a coach like ours and have not had all four corners weighed.

[Dick Simonis]

I'm guessing that all early PT's are overloaded on the rear axle.  However, if this was truly a serious problem there would have been some reports of problems....my guess would be early bearing failures.  With that in mind I just can't get to excited about it.  Of interest is that on the weight info plate, that information is handwritten not embossed which suggest (to me at least) that that is not an "engineered" number supplied by the axle manufacturer.

Be an interesting question to ask the folks at Beaver Coach.

[Joel Weiss]

As I noted in a previous post, my Michelin Tire dealer in Casper WY was an individual with a lot of knowledge and with "very strong opinions."  Although chewed me out for keeping my tire pressures too high, he wasn't the slightest bit worried about our being ~2,000 lbs over the rear axle rating.  He said that we were within the normal 10% safety margin and were exhibiting none of the symptoms of severe overload. I realize this isn't a guarantee of anything, but this guy seemed to know his business and was the kind who would have definitely spoken up if he thought there was an issue.

My assumption is that I probably am shortening the life of my axle bearings a bit, so maybe they will only go 200,000 miles instead of 500,000.  I'll probably never notice the difference. :K)