hitch on rear of 3900fb

[oldhdrider]

Hi folks,

My question. Would a Montana 3900fb support a class IV hitch and carry a Hydralift with a 800lb motorcycle? Total weight around 1100 lbs.

thank you

[JRTJH]

My thought would be "probably not". You're looking at 1100 lbs of weight "hanging" off the rear of the RV, attached about 24" forward of the rear (on the frame). That's about 250 lbs of hardware, plus the hydralift, plus the weight of the motorcycle. That much weight that far behind the axles will dramatically lighten your pin weight and possibly make the RV unstable to tow. The guidelines are to maintain the pin weight between 15 and 25% of the RV weight.

The frames on most fifth wheels are 10" or 12" box rail frames, built by Lippert and used by almost all the RV manufacturers. When we had our 26' Springdale fifth wheel the metal fabrication company that installed my hitch would only agree to a 3500 lb max towed load with 350 lbs of tongue weight. They said anything heavier than that just wouldn't work with the Lippert rail frame. We had 10" box rails on that RV. You've probably got 12" box or I beam rails on yours (12" I beam is what's advertised on the 2014 Montana models).

If you contact Keystone, their standard answer is, "We don't recommend installing a trailer hitch on our RV's. If I were you, I'd contact Lippert, explain what you're wanting to do and see what their take is on the plan. They would be able to give you much more information on how the frame is engineered and manufactured.

I would think if you're going to try to tow, you might be better off with a small trailer to put the bike on or to tow it with the front wheel in a carrier and the rear wheel on the ground.

[superdog404]

Here is one person who tows a boat from his Keystone.
http://www.keystonerv.org/forums/sho...?t=3703&page=2
There was also one more elaborate than this one where he completely removed the bike rack and made another but I can't find who that was. I have a couple pictures of it.

[oldhdrider]

Thanks John. We were at the rv show and I seen this model 5th wheel with a class 3 hitch. Because of the weight of my bike I'd have to have a class4. That is a lot of weight to have hanging off the back. I don't want to push it too much and I'm thinking I'm going to have to go another way. I want my bike 'and' be able to tow a vehicle. Maybe a toy hauler with a class 3 hitch?

Originally Posted by JRTJH

My thought would be "probably not". You're looking at 1100 lbs of weight "hanging" off the rear of the RV, attached about 24" forward of the rear (on the frame). That's about 250 lbs of hardware, plus the hydralift, plus the weight of the motorcycle. That much weight that far behind the axles will dramatically lighten your pin weight and possibly make the RV unstable to tow. The guidelines are to maintain the pin weight between 15 and 25% of the RV weight.

The frames on most fifth wheels are 10" or 12" box rail frames, built by Lippert and used by almost all the RV manufacturers. When we had our 26' Springdale fifth wheel the metal fabrication company that installed my hitch would only agree to a 3500 lb max towed load with 350 lbs of tongue weight. They said anything heavier than that just wouldn't work with the Lippert rail frame. We had 10" box rails on that RV. You've probably got 12" box or I beam rails on yours (12" I beam is what's advertised on the 2014 Montana models).

If you contact Keystone, their standard answer is, "We don't recommend installing a trailer hitch on our RV's. If I were you, I'd contact Lippert, explain what you're wanting to do and see what their take is on the plan. They would be able to give you much more information on how the frame is engineered and manufactured.

I would think if you're going to try to tow, you might be better off with a small trailer to put the bike on or to tow it with the front wheel in a carrier and the rear wheel on the ground.

[oldhdrider]

Hey superdog, thanks.

There must be an internet site that show which states you can tow a vehicle behind a 5th wheel. I'll have to try to find one. I really don't want to be limited though to where we can travel. We really like the big 5th wheels over the class a's. Been looking at the toy haulers to keep bike but then the wife won't have her RAV4. dang!! what to do....

Originally Posted by superdog404

Here is one person who tows a boat from his Keystone.
http://www.keystonerv.org/forums/sho...?t=3703&page=2
There was also one more elaborate than this one where he completely removed the bike rack and made another but I can't find who that was. I have a couple pictures of it.

[KanTC]

Originally Posted by oldhdrider

.....There must be an internet site that show which states you can tow a vehicle behind a 5th wheel. I'll have to try to find one.....

oldhdrider,

There's some info (& several discussions) already here on the forum Here's some to get you started:

http://keystonerv.org/forums/showthread.php?t=4707

http://keystonerv.org/forums/showthread.php?t=13889

http://keystonerv.org/forums/showthread.php?t=13118

http://keystonerv.org/forums/showthread.php?t=12369

http://keystonerv.org/forums/showthread.php?t=8229

http://keystonerv.org/forums/showthread.php?t=5437

If you don't find the answers you need, use the search feature... try: tandem towing -or- double towing -or- triple towing (as its sometimes called).

Hope this helps,
Terri, the Chevy co-pilot

[oldhdrider]

Thanks for the links. I went to and read them all. Lots of good stuff.
Answered some of my questions.

Originally Posted by KanTC

oldhdrider,

There's some info (& several discussions) already here on the forum Here's some to get you started:

http://keystonerv.org/forums/showthread.php?t=4707

http://keystonerv.org/forums/showthread.php?t=13889

http://keystonerv.org/forums/showthread.php?t=13118

http://keystonerv.org/forums/showthread.php?t=12369

http://keystonerv.org/forums/showthread.php?t=8229

http://keystonerv.org/forums/showthread.php?t=5437

If you don't find the answers you need, use the search feature... try: tandem towing -or- double towing -or- triple towing (as its sometimes called).

Hope this helps,
Terri, the Chevy co-pilot

[JRTJH]

Originally Posted by superdog404

Here is one person who tows a boat from his Keystone.
http://www.keystonerv.org/forums/sho...?t=3703&page=2
There was also one more elaborate than this one where he completely removed the bike rack and made another but I can't find who that was. I have a couple pictures of it.

I tow a Tracker Tournament TX 175 behind my fifth wheel. The RV is 30'5" long the boat is 17'9" and sits on a trailer that's just a tad over 21' long. The outboard hangs out behind the boat at a 45* angle which adds another 18-24". When hitched to my truck, the entire rig is 73' long. Many states restrict total length to 65'. Michigan (fortunately) is 75'. If I had a 40' fifth wheel and a crewcab long bed truck, I'd be pushing 90' long. So, there's much more to think about besides whether or not a hitch is "weldable" to the backend of the fifth wheel.

Total length on any fifth wheel over 30' is going to definitely be an issue with almost any boat and fifth wheel over about 35' is probably going to be an issue with a shorter flatbed trailer towing ATV's or motorcycles. It's amazing how fast length can "grow" when you start hitching things behind other things.....

In a state with a 65' limit, towing a 35' fifth wheel with a long bed crewcab(assume 7' is doubled up) you're already going to be at or slightly over 50' long. That only leaves 15' for the hitch (which extends about a foot behind the RV bumper and that means a 14' trailer. Most 5x8 flatbed trailers are 13' or longer, so the limiting factor for towing a trailer, boat or ??? behind many fifth wheels is total rig length, not weight, GCWR, pin weight balancing or being able to see behind the fifth wheel.

[oldhdrider]

Thanks again John, very good points and "total length" is definitely an issue that needs to be addressed. There may be limits in some states on whether or not you can operate a train on their highways.

Originally Posted by JRTJH

I tow a Tracker Tournament TX 175 behind my fifth wheel. The RV is 30'5" long the boat is 17'9" and sits on a trailer that's just a tad over 21' long. The outboard hangs out behind the boat at a 45* angle which adds another 18-24". When hitched to my truck, the entire rig is 73' long. Many states restrict total length to 65'. Michigan (fortunately) is 75'. If I had a 40' fifth wheel and a crewcab long bed truck, I'd be pushing 90' long. So, there's much more to think about besides whether or not a hitch is "weldable" to the backend of the fifth wheel.

Total length on any fifth wheel over 30' is going to definitely be an issue with almost any boat and fifth wheel over about 35' is probably going to be an issue with a shorter flatbed trailer towing ATV's or motorcycles. It's amazing how fast length can "grow" when you start hitching things behind other things.....

In a state with a 65' limit, towing a 35' fifth wheel with a long bed crewcab(assume 7' is doubled up) you're already going to be at or slightly over 50' long. That only leaves 15' for the hitch (which extends about a foot behind the RV bumper and that means a 14' trailer. Most 5x8 flatbed trailers are 13' or longer, so the limiting factor for towing a trailer, boat or ??? behind many fifth wheels is total rig length, not weight, GCWR, pin weight balancing or being able to see behind the fifth wheel.

[Bill & Deb]

Originally Posted by oldhdrider

Hi folks,

My question. Would a Montana 3900fb support a class IV hitch and carry a Hydralift with a 800lb motorcycle? Total weight around 1100 lbs.

thank you

One thing I am going to look into is mounting a bike lift to the front of my truck. May be using two, two inch receivers. Then it could be removed. I would try and keep the bike low so as to not block my view. Would be for a Goldwing. No idea how complicated it would be. But it should not be a weight issue with the 5'er connected.
Bill

[patagoniadave]

Originally Posted by JRTJH

.....If I were you, I'd contact Lippert....

Do they just do the base frame, or do they do all of the structure? I am dying of curiosity of how my rig is framed. It probably comes from drawing structural plans all the time at work, I just want to know, or even better, have a set of plans I can play around with in CAD. I know Keystone does not give these type of things out, but will Lippert?

[JRTJH]

Lippert builds the chassis, Keystone puts Dexter axles under it and then builds the superstructure using components from many sources, but primarily Lippert supplied doors, windows, etc.

Lippert does not build the walls, floor or ceiling.

As for drawings, as you already know, none are available, but on a cool morning when there's lots of dew, the "skeleton" of the RV is often visible where the dew collects on the outside skin at the metal framework of the walls. With careful measurement and drawings, over time, you could probably get pretty much all the superstructure "mapped out".

[patagoniadave]

Originally Posted by JRTJH

Lippert builds the chassis, Keystone puts Dexter axles under it and then builds the superstructure using components from many sources, but primarily Lippert supplied doors, windows, etc.

Lippert does not build the walls, floor or ceiling.

As for drawings, as you already know, none are available, but on a cool morning when there's lots of dew, the "skeleton" of the RV is often visible where the dew collects on the outside skin at the metal framework of the walls. With careful measurement and drawings, over time, you could probably get pretty much all the superstructure "mapped out".

What is this "Dew" you speak of? ;-)

[limey]

Apart from the overall length limitations, many states simply do not allow towing behind a 5th wheel. A way around this (but not the overall length) is to go with a "swivel wheel" trailer. This is not considered a trailer for towing regulations - and makes sense for towing behind a 5th wheel as it allows easier reversing! There are several manufacturers if you do a "Google" search.

I am thinking of putting one behind our Montana so I can bring one of my motorcycles with me on the road!