TOWING CAPACITY

[exav8tr]

That's What I'M talking about, Orv. The actual CAPABILITY of my unit.......

[richfaa]

Now I am a rating and specification guy but having worked in the aviation field for 37 years. I know that they can be legally changed by the manufacturer. Phil's example is a good one and accurate. I refer to the ratings and spec's on a OEM vehicle and they should be adhered to.IMO in Steve's case the manufacturer has not changed the sticker but the ratings and spec's have changed. I have no clue as to the legalities but would feel Ok to defend that the ratings have changed...sticker or no sticker change.

[up2nogood]

quote:Originally posted by richfaa

Now I am a rating and specification guy but having worked in the aviation field for 37 years. I know that they can be legally changed by the manufacturer. Phil's example is a good one and accurate. I refer to the ratings and spec's on a OEM vehicle and they should be adhered to.IMO in Steve's case the manufacturer has not changed the sticker but the ratings and spec's have changed. I have no clue as to the legalities but would feel Ok to defend that the ratings have changed...sticker or no sticker change.

This has been a heavly discussed topic. I see that you are starting to entertain the idea of upgrading to change the rating or capacity if you will.Changing 6k to 7k axles does nothing to change the GVWR on the weight tag, but certainally changes the GVWR of the 5ver. With that being said now what has he accomplished?? Its going to have a larger axle,brakes and bearings thus the capacity for more weight, now can the frame, tires ,etc handle the additional weight ?? Well he can make arguement that his 3400 is the same as the 2008 3400 that has the 7k axles. I think you can see where this is going. Is It legal that now he is over his GVWR on the weight tag, I have not a clue nor a concern, all I know is he has made the 5ver more safe for the additional weight.

I think you already know my stand on 3/4 ton and 1 ton as far as weight ratings go.I feel the same way as above.

[richfaa]

I did ask the question at the Tampa RV show last winter to a high ranking Montana person. The only thing changed was the axles and everything associated with them so I took that to mean that the upgraded axles would indeed make it that same as the 08/09 3400 built with the 7K axles..execpt...for the sticker on the side. As for the rest of the camper..there is doubt in my mind that the tires and frame were sturdy enough for the 6K axles. Legal??? these are not commercial vehicles subject to those regs..but would not care to be a test court case on the add on VS weight tag issue. In terms of the trucks and campers I stand by staying within the ratings and spec's of the OEM units with no add on's. This is a legal issue far beyond my understanding.Yes I think the addition of the7K axles would make my 06 3400 a safer vehicle.
Which is why I am considering doing it.. I will be asking more questions at the fall rally.

[billhoover]

quote:Originally posted by Bob & Lee

The question I have in relation to the weight is in the Ford spec book it lists the cargo weight and the pulling weight . What is it when there is a - in the block as in the payload SRW 4X4 max GVWR all listed and some have the - is that NA or what ? they have a 11,500Lb F350 SRW in the options but no payload. how do you read this thing.

Thanks
Bob

If I understand what you are trying to determine...here you are:

- Cargo capacity is on the Tire and Loading Information sticker on the left rear door frame...gives the cargo capacity for THAT truck to the nearest one pound as it leaves the factory.

- Tow capacity is the GCWR minus the actual weight of the truck when towing.

[up2nogood]

quote:Originally posted by richfaa

I did ask the question at the Tampa RV show last winter to a high ranking Montana person. The only thing changed was the axles and everything associated with them so I took that to mean that the upgraded axles would indeed make it that same as the 08/09 3400 built with the 7K axles..execpt...for the sticker on the side. As for the rest of the camper..there is doubt in my mind that the tires and frame were sturdy enough for the 6K axles. Legal??? these are not commercial vehicles subject to those regs..but would not care to be a test court case on the add on VS weight tag issue. In terms of the trucks and campers I stand by staying within the ratings and spec's of the OEM units with no add on's. This is a legal issue far beyond my understanding.Yes I think the addition of the7K axles would make my 06 3400 a safer vehicle.
Which is why I am considering doing it.. I will be asking more questions at the fall rally.

Well, we halfway agree that is a start.

Good luck on the axle change. I have the 2008 3400RL with the MorRyde suspension and hitch pin alot more smooth towing then my previous Montana 2980RL that was shorter and lighter.

Sorry to the OP kind of wandered off topic here.

Would hate to see you not get the 3400 its a great 5ver, we could not find a floor plan we liked better than the 3400.

As far as your truck goes you are probably over on your pin weight,I tow my 3400RL with a 1 ton Superduty SRW, some will say we are in 1 ton dually range. I won't argue ,but I don't need to agree.My biggest concern and I believe the weakest link is your tire ratings on a SRW with that kind of pin weight. My biggest concern is how much weight I have sitting on those rear tires.My rear axle weight is 3220 full tank, etc and a few other items. I have not weighted my 5ver yet, so I took the 20 percent of the GVWR ( 15,500 lbs ) which is 3100 lbs, so combined weight of 6320, and I truly think my pin weight is less than 3100 lbs,some may chime in that have an exact pin weight on the 2008 3400RL. My tires are E rated @ 3640lbs for a total weight rating of 7280 lbs.900 lbs under my total weight. The rest for ME is no problem handling braking etc. I feel comfortable towing with my truck. Some say it is a white knuckle experience towing these bigger 5vers with a 3/4 or 1 ton SRW.Bottom line is the weight numbers will not work on a 3/ton Superduty towing a Montana 3400RL. A 1 ton will get you closer, but I repeat your tires in MY opinion is the weakest link. Take it for what it is worth and check out this forum theres alot of SRW towing the 3400

[ALAN]

Now that I have upset the apple cart with my original question, you guys are great with your comments and insight, I offer an alternate question. Would air bags accomplish my goal as well as new leaf springs? I always thought that air bags simply leveled the truck nothing more. Now I have two installers telling me that I do not want the harsh ride of the additional leaf spring when with air bags I could adjust the ride when not pulling the 5th wheel and accomplish the same goal.

Comments?

Alan & Kathy

[up2nogood]

[quote]Originally posted by ALAN

Now that I have upset the apple cart with my original question, you guys are great with your comments and insight, I offer an alternate question. Would air bags accomplish my goal as well as new leaf springs? I always thought that air bags simply leveled the truck nothing more. Now I have two installers telling me that I do not want the harsh ride of the additional leaf spring when with air bags I could adjust the ride when not pulling the 5th wheel and accomplish the same goal.

Comments?

This is where the apple cart will get upset. I make the arguement leaf springs are the difference between your truck and mine a 1 ton. Now is a 1 ton Superduty weight ratings high enough for that 3400RL you are on the border. I will repeat tires are my main concern. I also have air bags to take out a little of the squat. That extra leaf springs is not going to change the ride that much after all they are a truck. I have always said I am not going to start spouting weight numbers of the truck,. I know them and I know what Ford tells me the truck will handle, I also know from experience how my truck handles a fifth wheel of this weight, and I will repeat the tire ratings were my big concern. Will a dually handle it better of course it will.

[sreigle]

quote:Originally posted by Charlie

Well put Steve....however the ratings and warranties go hand in hand. It is each individuals choice to change the TV's capabilities.

What you say is fact, Charlie. But, you know, not once, not even one time, has any dealer ever asked me how much weight I'm towing or how much pinweight. But, then, I've never had a failure of any part that might be impacted by the weight towed or carried.

I agree what Richfaa said about increasing capabilities. My Montana has the same weight carrying capability as the later Montanas built a couple of months later with the 7k axles. In fact, I may have even more since mine have the thick wall 7k axles rather than the thin wall 7k axles I think come on the Montana (not sure about that). I was told that makes them more resistant to jacking damage. In any case, we were not over the ratings for the 6k axles but were very close. And we were having some axle problems with the Montana. So we swapped out the axles for the heavier ones. And we got self-adjusting brakes in the process. Bottom line is the sticker on the wall says the same as it did before. I checked. But the trailer is now capable of higher weights since it now is no different than the slighly newer Montanas as far as frame and running gear. For what it's worth, we also went with the 7k springs with the 7k axles. It's possible to use the old 6k springs with the heavier axles but we didn't see any value in doing that other than slighly lower cost.

Bottom line, capability changes, official rating stickers do not. To tell the truth, I'm more concerned with actual functional capability than I am with that sticker.

[up2nogood]

quote:Originally posted by sreigle

What you say is fact, Charlie. But, you know, not once, not even one time, has any dealer ever asked me how much weight I'm towing or how much pinweight. But, then, I've never had a failure of any part that might be impacted by the weight towed or carried.

I agree what Richfaa said about increasing capabilities. My Montana has the same weight carrying capability as the later Montanas built a couple of months later with the 7k axles. In fact, I may have even more since mine have the thick wall 7k axles rather than the thin wall 7k axles I think come on the Montana (not sure about that). I was told that makes them more resistant to jacking damage. In any case, we were not over the ratings for the 6k axles but were very close. And we were having some axle problems with the Montana. So we swapped out the axles for the heavier ones. And we got self-adjusting brakes in the process. Bottom line is the sticker on the wall says the same as it did before. I checked. But the trailer is now capable of higher weights since it now is no different than the slighly newer Montanas as far as frame and running gear. For what it's worth, we also went with the 7k springs with the 7k axles. It's possible to use the old 6k springs with the heavier axles but we didn't see any value in doing that other than slighly lower cost.

Bottom line, capability changes, official rating stickers do not. To tell the truth, I'm more concerned with actual functional capability than I am with that sticker.

I find this a little crazy, I agree with what you are saying. Here is the problem its okay for some to upgrade a 5ver to handle more weight thus more safe, but heaven forbid upgrade a truck to handle more weight thus more save. You come out with the same results more capacity, but no change in the ratings.

[up2nogood]

I have been waiting to get my 2008 3400RL back from the dealer, got it today. Had a couple things done to it before it went off warranty in November.Took it to the scales before I took it home. I have the Onan 5500 LP generator, High gloss exterior supposedly heavier,Slide awnings on all four slides, MorRyde pin box. I am mentioning these things because of the increase in weight of the standard model. My 5ver is loaded to travel tools,chairs,camp stove etc. The only thing needed is food in the fridge, canned goods already in the 5ver, and our clothes Here are the weights :

Truck 1999 Superduty 350 SB CC 7.3 Diesel Full tank, hitch etc, 1 person in truck

Front Axle Truck 4580 lbs.
Rear Axle Truck 3220 lbs.
Total 7880 lbs.


Truck and 5ver 20,620 lbs
5ver 12,740 lbs.

Pin weight 2420 lbs. ( quite a bit lighter than the 20%. The GVWR of the 5ver is 15,500 lbs which would be 3100 lbs. pin weight @ 20% The 2008 3400RL is advertised at 11800 Dry here again to me looks like Keystone is pretty close on there numbers. I am still 2760 lbs. from GVWR of 5ver. I would say with the DW and a full fridge and clothes I could increase the load by as much as 400 lbs., and not all added to the pin weight.

What I am most curious about is how these numbers compare to other 2008 3400RL's

I posted this here to give the op an idea what kind of real weight he is looking at. Something I wanted since buying the 3400

[billhoover]

If I'm reading what you are saying correctly, you are very close to the 20% recommended for PW. That 20% is 20% of the trailer when actually loaded, not the trailer's GW. Therefore, 20% of your loaded trailer (12,740) is 2548, so at 2420, you are only 128 different than recommended.

[ALAN]

You raise another interesting question. I am not sure where you got the 12740# for a loaded 3400RL, but I wonder if the following analysis is correct. According to the Keystone web site, the max. wt for a 3400RL is 15930#(ship wt of 12700+CC of 3230#). These numbers result in the published pin wt being about 15% of the total wt of the trailer. If we assume that the distribution of this wt is between three points touching the ground, the two axles on the trailer and the rear axle of the tow vehicle, then we arrive at the following numbers: axles of trailer 6750 each or 13500#, tow vehicle 2430 (pin wt). I believe these numbers match the pin wt and axle capacity of the trailer.

Now this raises the interesting question noted above. If this is correct, then distribution of the wt in the trailer is very important
to achieve these numbers. I wonder if you weight your trailer to achieve pin wt and this number exceeds the published pin wt, then you may have an unbalanced trailer. Does not solve my initial question but does make playing with numbers interesting.

This could drive one crazy. I thought the idea was to have fun.

Alan & Kathy

[up2nogood]

quote:Originally posted by billhoover

If I'm reading what you are saying correctly, you are very close to the 20% recommended for PW. That 20% is 20% of the trailer when actually loaded, not the trailer's GW. Therefore, 20% of your loaded trailer (12,740) is 2548, so at 2420, you are only 128 different than recommended.

I think you missed what I said. 20% of the rated GVWR of the 5ver which is 15500, which is 3100 lbs.If I have heard it once I have heard it a thousand times on these forums the rule of thumb is 20% of the GVWR of the 5ver that does not mean that the actual weight of the fiver is 15500 only a number to guess what your pin weight is.Countless times I have heard don't use you dry weight use 20% of your GVWR. IF I would of used my dry weight of 11,800 I would have been alot closer to my actual pin weight not someones theory using 20% of the GVWR.

This is the first time I have read someone say 20% of the actual weight of the 5ver, which makes a whole lot more sense. All I have read is 20% of the GVWR which may or may not be the actual weight.

[up2nogood]

quote:Originally posted by ALAN

You raise another interesting question. I am not sure where you got the 12740# for a loaded 3400RL, but I wonder if the following analysis is correct. According to the Keystone web site, the max. wt for a 3400RL is 15930#(ship wt of 12700+CC of 3230#). These numbers result in the published pin wt being about 15% of the total wt of the trailer. If we assume that the distribution of this wt is between three points touching the ground, the two axles on the trailer and the rear axle of the tow vehicle, then we arrive at the following numbers: axles of trailer 6750 each or 13500#, tow vehicle 2430 (pin wt). I believe these numbers match the pin wt and axle capacity of the trailer.

Now this raises the interesting question noted above. If this is correct, then distribution of the wt in the trailer is very important
to achieve these numbers. I wonder if you weight your trailer to achieve pin wt and this number exceeds the published pin wt, then you may have an unbalanced trailer. Does not solve my initial question but does make playing with numbers interesting.

This could drive one crazy. I thought the idea was to have fun.

Alan & Kathy

Alan, heres how I got these numbers, about a month ago I took just my truck to the scales full tank, hitch, propane bottle in the bed etc basically ready to tow, but with just me in the truck. The truck weighted 7880 lbs.Today on the same scales with 5ver hooked up my weight was 20,620 the difference was 12,740. I figured my pin weight by weighing the truck on the scales with the axles of the 5ver off of the scales, and that weight was 10,300 the difference being 2420.

[ALAN]

Thanks for the explanation. That makes more sense. All these numbers could drive you up a wall, but I guess we need to at least be aware of the data and make our decision as to how we will react.

Appreciate all the comments. As I expected this is a great forum.

Alan & Kathy

[sreigle]

My understanding is that pinweight for a fifthwheel is recommended to be between 20% and 25% for good handling characteristics. Not just 20% but the range of 20% to 25%. Anywhere in that range is supposedly a good thing. Ours is actually slightly below the range at 19.6%. Our 2003 3295RK was at 23.0%. Those models carry a heavy pinweight. Both models handle very nicely for us.

To add a comment to my axle update situation.. we updated axles to stop tire and axle problems, not so we could add more weight. We were under the ratings of the 6000 lb axles but just barely. I suspect those axles are not built with a rating cushion like trucks are. We were close enough that any sudden trauma (potholes, etc) was tough for the lighter axles to handle.

[TLightning]

The GM manual says 5th wheel PW should be between 15% and 25%.

[dnichol]

I have towed various trailers hawling different things(bulldozers,tractors etc.)and if the load is balanced right with regard to pin weight you can tow over your rating fairly easy with late model 3/4 or 1 ton trucks.Right now I am towing 09 Montana 3665RE with 3/4 ton chevy & it tows good. The only thing that concerns me is the single axle on the truck. If I upgraded truck I would probably get a 1 ton dually. This is my 8th rv & so far the best.

[KathyandDave]

More grist for the mill...my opinions only, which are the results of my investigations. Your mileage may vary.

It seems to me that all of the calculations are simply to identify the weakest link (constraint), which will be the actual limit. This includes permit and drivers licence.

The listed towing capacity of the TV pertains to OEM equipment weight limits for engine power and torque, braking, steering and handling, with a pinch of warranty management thrown in. The axle capacities pertain to how much weight the axle will support. For the rear of the TV, this will include the pin weight. So, you could beef up the TV's rear axle with after-market springs, balloons or rubber bumpers to support more pin weight, but the gross capacity of the TV wouldn't change. Similarly for tires, with the added constraint of speed.

I calculate according to the actual weights measured on the scale, then compare to the target values. None of the values can exceed a rated maximum or be less than a minimum, as in the case of pin weight. To find pin weight, measure the TV's rear axle weight with and without the trailer, under similar load conditions. Subtract the "without" from "with" to get the pin weight. Measure the trailer axles together, without the TV (drive the TV forward off the scale). Add the pin weight to the axles' weight to get the trailer gross. According to the Montana owners manual, the pin weight should be 20-25% of the gross, while according to the GM manual, it should be 15-25%. So, balancing the load in the trailer is important. We are running at about 20%.

The manual for our TV states that the combination of TV and trailer must be less than 10,659kg (23,500lbs). Others have noted that this limit seems to vary according to whether it's an advertising brag or a warranty cutoff!

In Ontario, I can drive an RV combination up to 11,000kg (24,000lbs) with a general operators "G" license. So, I make sure that our entire rig weighs less than this value. If I upgrade my license to an "A", suitable for tractor trailers, then this would no longer be the limiting factor. The last time I weighed the rig, with all souls aboard and a full load of diesel, we weighed 10,860kg, just 160kg (about 350lbs) shy of the limit for my license and just over the rated limit for the TV.

In Ontario, the weight of the combination is carried on the permit of the TV and the rules for commercial vehicles pertain if the combination is used for business purposes (e.g., a landscaping company towing a trailer of equipment). Since the trailer is not used for business purposes, the weight of the Monty is not considered, which substantially reduces the permit fee and the headaches that come with a commercial permit!

All things considered, we have well-balanced rig that can pull up hills, stop and steer safely. A heavier SOB would exceed the capabilities of the Sierra and would require me to get an "A" license. So, we'll stick with this for a while.