Undersized axles on Momentum 320G or just poor design?

[chikenstiker]

I raised my Goosebox up above the "Standard" position like RoyB did and we'll see in the morning how it looks. Heading out for a 10 day trip. I have lots of water and soda under the bed and the 100 lbs heavier hitch and not dirt bikes, lets see how it does....

[RoyB]

I raised my Goosebox up above the "Standard" position like RoyB did and we'll see in the morning how it looks. Heading out for a 10 day trip. I have lots of water and soda under the bed and the 100 lbs heavier hitch and not dirt bikes, lets see how it does....

Back to my original posts, my camper towed better WITH weight in the garage. Without weight it seems to sway more. I attributed it to too much pin weight on my 2500. My 3500 handles the trailer much better, but I do notice the trailer moving around back there with no toys, even though it's not pushing the truck around now. I had towed 2500 miles over 2 weeks with my Harley (950lb+) and full tank of water without any issues with my 2500. As soon as I took the cycle out the truck was getting pushed around and the trailer was moving around a lot.

I could only assume the toys/weight in the garage lower the center of gravity of the trailer which helps it tow straighter. Maybe changes the camber on the axles? My original issue was too much weight on the axles with just a Harley + water and never meeting the GVWR.

I don't think I've towed with a toy + Ram 3500 yet. We were going 4-wheeling this weekend but decided to wait until my wife feels better. We have another trip in 2 weeks though. Might throw a single ATV in to see how the 3500+ toy tows.

[chikenstiker]

Back to my original posts, my camper towed better WITH weight in the garage. Without weight it seems to sway more. I attributed it to too much pin weight on my 2500. My 3500 handles the trailer much better, but I do notice the trailer moving around back there with no toys, even though it's not pushing the truck around now. I had towed 2500 miles over 2 weeks with my Harley (950lb+) and full tank of water without any issues with my 2500. As soon as I took the cycle out the truck was getting pushed around and the trailer was moving around a lot.

I could only assume the toys/weight in the garage lower the center of gravity of the trailer which helps it tow straighter. Maybe changes the camber on the axles? My original issue was too much weight on the axles with just a Harley + water and never meeting the GVWR.

I don't think I've towed with a toy + Ram 3500 yet. We were going 4-wheeling this weekend but decided to wait until my wife feels better. We have another trip in 2 weeks though. Might throw a single ATV in to see how the 3500+ toy tows.

Interesting Info.

My trip that had the worst sway to date was 16,820 lbs total (20 lbs over max) and only a 14.7% Pin Weight. I had as mush stuff as I possibly could moved to the front. I traveled down windy hills under the speed limit and with my hand resting on the trailer brake because it would get so bad. that was with the F350 CCLB and I did find out while at the scales that the truck was over weight. Many don't realize how little carrying opacity these trucks really have, mine was only 3280 lbs on a 1 Ton. LOL So 2,480 Pin, 4 people, dog, tools, fuel, fuel for dirt bikes (cuz I can't carry in trailer or pin gets lighter), etc. all adds up.

[RoyB]

Interesting Info.

My trip that had the worst sway to date was 16,820 lbs total (20 lbs over max) and only a 14.7% Pin Weight. I had as mush stuff as I possibly could moved to the front. I traveled down windy hills under the speed limit and with my hand resting on the trailer brake because it would get so bad. that was with the F350 CCLB and I did find out while at the scales that the truck was over weight. Many don't realize how little carrying opacity these trucks really have, mine was only 3280 lbs on a 1 Ton. LOL So 2,480 Pin, 4 people, dog, tools, fuel, fuel for dirt bikes (cuz I can't carry in trailer or pin gets lighter), etc. all adds up.

Yikes.
My Limited 3500: 3682 Payload, 24,992 towing. That's with every option it can come with too.

Both your truck and trailer were overweight and you are surprised you had sway? In my experience, the proper sized truck eliminates a lot of the trailer sway issues. I had a heavy 3500lb pop-up and a Tacoma. It pushed that little truck around. I upgraded to a Tundra and it pulled the hell out of that popup. We then upgraded to a 28' Quad bunk (33' OAL) and the Tundra struggled with that. Traded that for a Ram 2500 and I never noticed it behind the truck. Then came the 5th wheel. The 2500 did OK as long as the trailer was loaded a certain way. Once all the weight was on the truck, it pushed the truck around too much for me. Que the 3500....No problems empty now. I am limited for a while on upgrading because of space at this point This was over the course of 14 years mind you.

[chikenstiker]

Yikes.
My Limited 3500: 3682 Payload, 24,992 towing. That's with every option it can come with too.

Both your truck and trailer were overweight and you are surprised you had sway? In my experience, the proper sized truck eliminates a lot of the trailer sway issues. I had a heavy 3500lb pop-up and a Tacoma. It pushed that little truck around. I upgraded to a Tundra and it pulled the hell out of that popup. We then upgraded to a 28' Quad bunk (33' OAL) and the Tundra struggled with that. Traded that for a Ram 2500 and I never noticed it behind the truck. Then came the 5th wheel. The 2500 did OK as long as the trailer was loaded a certain way. Once all the weight was on the truck, it pushed the truck around too much for me. Que the 3500....No problems empty now. I am limited for a while on upgrading because of space at this point This was over the course of 14 years mind you.

Nope I wasn't surprised! I've had sway with this trailer since brand new and empty! I knew I was loaded the heaviest I would usually be that specific trip which is why I stopped at the scales. I still get some sway even with a Ram 3500 DRW!

My very first trip with the trailer was the day after I picked it up, only had it a bit over half loaded and just mountain bikes and chairs in the garage and the sway was crazy! My dad was following me and 1st thing out of his mouth when we got to the campsite was about how the trailer was all over the place! I assumed I just didn't have enough up front since it wasn't completely set up and dialed in, but it never got much better no matter what I stuffed up front and under my bed.

I had a 2006 Attitude Bumper Pull Toy Hauler and my buddy had a 2005 Eclipse Toy Hauler (both same company) both of the same model, they were almost exact in every single way! Mine swayed alot while towing his did not. One day sitting there drinking my beer I noticed something, his wheels looked like they were in a different spot. Sure as ****, his wheels were exactly 6" closer to the rear o his trailer than mine even though our trailers were the same overall, interior, gas station, everything. So I sold that trailer and bought a new Sandstorm and paid very close attention to where the wheels were (farther back) and that trailer towed like a dream with 0 sway!

New to 5th wheels I never thought about it and when I measure "my" 320G wheel placement compared to other brands of the same size and larger 351 and 349s my wheels are closer to the center of the trailer. Carbon 338 (Same overall length) the wheels are 14" closer to the back. GD 349/351 2.5' Longer overall yet wheels are the same exact distance as 320G from the back so they have 30" more body in front of the wheels and thus more Pin Weight too.

320G is a bad design and too "balanced"...

PS. Your 3500 is probably close to max weight too? Fuel, 2 people, and pin weight alone is about 3,350 and any tools, floor matts, dogs, wood in bed, hitch, etc will add that last 300 lbs. It's crazy how fast it adds up. I always thought with a 1 ton I could carry the world. LOL

[RoyB]

Looking at my last numbers:

Loaded, ready for camping (900lb bike, 80 gallons water= approx 1500 lbs)

• Hitch: 2,400 lbs (14.80%)
• Axles: 13,800 lbs
• Total: 16,200 lbs.

Removing the bike put 480 lbs back to the pin based on my original numbers. So in theory:

Loaded, ready for camping (No bike; 80 gallons water)

• Hitch: 2,880 lbs (18.80%)
• Total: 15,300 lbs.

That gives me 800 lbs capacity in the truck. Payload factors in 1 passenger and vehicle fuel. My wife is not 800 lbs. I don't have my dog anymore, and I don't carry much in the truck. Without a toy in the camper I don't need to bring extra fuel in the truck.

IF I brought a toy, my pin is 480 lbs less, increasing my available payload to 1280 lbs. 6x5 gallon gas, 3 passengers (150ea), some wood (200) and some straps, misc stuff= 1100 lbs. I still have head room on the payload with a loaded up Ram 3500+ toys in the 320G.

[chikenstiker]

Nice, sounds like you carry a lot less than I do. I thought truck weight was empty tank, but that's better if it's not. I carry a lot of tools and tow straps and such as I'm out in the boonies a lot.

When GD had me empty my trailer of everything except kitchen 1/2 fuel tank, full water and full LP I still only had a 15.8% pin...

Have a great weekend!

[RoyB]

Just an update. I called a couple dealers about upgrading to 8K lb axles. They all sounded incompetent on this work.

I emailed Morryde and got pricing for their IS. They are booked until next year.


Tandem 8K axle with Drums= $5800+ tax
Tandem 8K axle with Disk= $8600+ tax

I am tempted to do the upgrade with drums at their facility. I can't see spending the extra $2800 for disks. While having the disks would be nice, I feel the trailer stops adequately with the drums. I will pay closer attention to braking next weekend when we head out.

I will call some trailer service companies and see what they say. Would assume they can handle changing axles better than an RV dealer would. If I can upgrade to 8K lb + disk for the same price as the IS 8K drum I would probably do that. I can't see the IS making that huge a different even though I am sure it is much better than leafs.

[RoyB]

So I see Nitro has a very similar model now. The XLR Nitro 321. Identical floor layout and looks like the same length. Look how far back the wheels are. Granted the unit isn't as nicely appointed as the 320G, I assume it would tow and load better. I think GD should be repairing our trailers by moving the axles back.

[ncitro]

RoyB I went down this rabbit hole and was close to booking with MorRyde. howson has the IS and can probably speak better but I believe other than general ride the main benefit has to do with supporting weight when you go over bumps and pot holes. Rather than all that weight being on one tire on the side it stays distributed. I could be way off, it was a while ago I did the research.

Axles are pretty cheap and not difficult to change if you have the space and some jacks. I was also considering "axleless axles" on etrailer to create my own poor man's IS. In the end I decided to do a disc break upgrade with Performance Trailer Breaking at the national rally and had them upgrade my axles at the same time. I can say my rig stopped reasonably before but it's amazing now. I'm convinced it's how all trailers should be made.

[howson]

RoyB -- huge difference with the IS. Many threads and testimonials here-- only issue is quality of the install can be questionable. Jimmer has the latest experience to my knowledge.

100% advocate for disc brakes. Worth every penny IMO.

[acoleman43]

RoyB -- huge difference with the IS. Many threads and testimonials here-- only issue is quality of the install can be questionable. Jimmer has the latest experience to my knowledge.

100% advocate for disc brakes. Worth every penny IMO.

IS is a lot of pennies

[RoyB]

RoyB I went down this rabbit hole and was close to booking with MorRyde. howson has the IS and can probably speak better but I believe other than general ride the main benefit has to do with supporting weight when you go over bumps and pot holes. Rather than all that weight being on one tire on the side it stays distributed. I could be way off, it was a while ago I did the research.

Axles are pretty cheap and not difficult to change if you have the space and some jacks. I was also considering "axleless axles" on etrailer to create my own poor man's IS. In the end I decided to do a disc break upgrade with Performance Trailer Breaking at the national rally and had them upgrade my axles at the same time. I can say my rig stopped reasonably before but it's amazing now. I'm convinced it's how all trailers should be made.

When I price 8K lb axles and springs it gets pretty pricey. 6K+ I am not sure if springs are needed?

RoyB -- huge difference with the IS. Many threads and testimonials here-- only issue is quality of the install can be questionable. Jimmer has the latest experience to my knowledge.

100% advocate for disc brakes. Worth every penny IMO.

Can you comment on the "quality of the install"? I wonder if your brakes were too small for the rig. I assume the momentum with higher GVWR has larger brakes. I do find the brakes are less than adequate when they are cold. Once warmed up they seem ok.

[howson]

When I price 8K lb axles and springs it gets pretty pricey. 6K+ I am not sure if springs are needed?



Can you comment on the "quality of the install"? I wonder if your brakes were too small for the rig. I assume the momentum with higher GVWR has larger brakes. I do find the brakes are less than adequate when they are cold. Once warmed up they seem ok.

Long story hard to summarize.

https://gdrvowners.com/forum/operati...ts-post-1-of-3

https://gdrvowners.com/forum/operati...year-endurance

https://gdrvowners.com/forum/operati...-along-the-way

Enter MORryde IS site:gdrvowners.com or just MORryde site:gdrvowners.com into your favorite search engine (Google, DuckDuckGo, etc) and you'll be rewarded with a long list of threads to investigate.

[Cate&Rob]

With reference to ncitro Neil's post #160 . . . MORryde offers a fully independent suspension. This means that when going over a bump or pothole (on one side), all the weight is momentarily supported by only one tire and suspension. This is why the MORryde system is so "substantial". In a conventional trailer suspension, part of the load is transferred to the other wheel through the center equalizer.

Where this becomes a problem is during braking. Because RV suspension went to overslung springs rather than the traditional underslung springs, to gain ride height without really understanding the affect on suspension geometry . . . a traditional trailer suspension with equalizer actually lifts the front axle during braking. There used to be an LCI Correct Track video that (inadvertently I think) clearly showed this. Fully independent suspension (like MORryde) would be much more efficient under heavy braking . . . sharing the load amongst all tires rather than just two.

BTW . . . I also agree that EoH disc brakes is the best $2500 you can spend on towing safety. The improvement over 1950s technology electric drum brakes is simply amazing. Particularly on the second or third apply where the drums have overheated and the vented discs are still doing fine.

Rob