Increasing the carrying capacity of a Trillium

[David Tilston]

My Trillium has a stated GVW of 2000 lb. The trailer has a dry weight of about 1500 lb. This does not leave much room for cargo.

Can this be increased? Even 2500 lb would help.

[cpaharley2008]

The trailer's capacity is a function of it's parts, the axle, frame,tires. Exceeding any of these limits is not recommended, particularly if there is an accident.

[David Tilston]

The question I am asking is, what parts do I need to replace to get a higher capacity?

The tires are marked as 1009 lb, or 2018 lb total. They will have to be replaced. The hitch is marked 2000 lb GTW. That will have to be replaced.

Anyone know where on a Trillium 4500 the capacity of the axle is marked, or what The stock capacity was?

What else would I need to change? Other then the hitch, would frame mods be required?

[cpaharley2008]

It would appear that all the parts would need to be upgraded, as the weakest point would be that which wasn't. Not sure how you can upgrade your frame other than replacing it, but that would be the weakest point if your upgraded everything else. If you went to a 3500# axle/hitch/tires you will still need to upgrade the frame.

[floyd]

Originally Posted by David Tilston

The question I am asking is, what parts do I need to replace to get a higher capacity?

The tires are marked as 1009 lb, or 2018 lb total. They will have to be replaced. The hitch is marked 2000 lb GTW. That will have to be replaced.

Anyone know where on a Trillium 4500 the capacity of the axle is marked, or what The stock capacity was?

What else would I need to change? Other then the hitch, would frame mods be required?

I would make the changes myself, but if you don't have the tools and skills to do so, it would be easy to simply remove the body from the frame and order a trailer of the appropriate size, then just bolt it on to it's new chassis. You would be surprised how cheap that can be, I have a source which would build it for under a thousand dollars. you could probably have it done for under 15.
Now this is assuming that your 4500 is constructed like the 1300 and is bolted to it's frame.

[David Tilston]

It is bolted to the frame. Looks like eight big bolts. Not sure what size, could be 1/2".

It is a bit of a radical solution, I have a neighbor who regularly builds trailers and small dump trucks in his back yard. He has been very helpful. In fact he has offered to paint my trailer for free, as long as I buy the paint and do all the sanding and masking.


I suppose that a 33 year old trailer may be a bit tired by now. New running gear could be called for.


I will have to think this over.

[Roger C H]

Do you have an anvil or rock collection that you want to take to collectors' meets?

We had enough for living two months in our 1300 and it weighed 1840#.

[lamimartin]

Originally Posted by David Tilston

It is bolted to the frame. Looks like eight big bolts. Not sure what size, could be 1/2".

It is a bit of a radical solution, I have a neighbor who regularly builds trailers and small dump trucks in his back yard. He has been very helpful. In fact he has offered to paint my trailer for free, as long as I buy the paint and do all the sanding and masking.

I suppose that a 33 year old trailer may be a bit tired by now. New running gear could be called for.

I will have to think this over.

Some versions of Trillium 4500 even had a recall because the frame used to fail over time http://www.fiberglassrv.com/forums/f...nfo-32242.html The frame steel is very thin and it may crack at the axle or the front end as it curves up to get to hitch ball level. Changing the axle and reinforcing the current frame will not legally increase load capacity. Any added weight will in fact reduce it.

So the frame, suspension and tires must be upgraded to make it safe for higher load. Unfortunately, some insurance company may not agree to insure an RV that has been modified or may not pay in case of an accident if they find out it is not original. Resale value of a modified frame may be drastically reduced because the insurance factor.

In my humble opinion, the best way to manage this problem is to look at the existing trailer and find material changes that can reduce weight and replace defective axle components by same weight, not heavier.

[floyd]

Originally Posted by lamimartin

Some versions of Trillium 4500 even had a recall because the frame used to fail over time http://www.fiberglassrv.com/forums/f...nfo-32242.html The frame steel is very thin and it may crack at the axle or the front end as it curves up to get to hitch ball level. Changing the axle and reinforcing the current frame will not legally increase load capacity. Any added weight will in fact reduce it.

So the frame, suspension and tires must be upgraded to make it safe for higher load. Unfortunately, some insurance company may not agree to insure an RV that has been modified or may not pay in case of an accident if they find out it is not original. Resale value of a modified frame may be drastically reduced because the insurance factor.

In my humble opinion, the best way to manage this problem is to look at the existing trailer and find material changes that can reduce weight and replace defective axle components by same weight, not heavier.

Seriously; do you know of a single bonafide case of someone being denied insurance or payment due to an upgrade in the frame or suspension?
I have been building cars, trailers and light trucks for 40 years including my own chassis designs, and I have never been denied coverage.
I don't know of anyone personally who has been denied coverage either, and I know many builders and hobbyists.
Of course, I live in the U.S.

[David Tilston]

Originally Posted by Roger C H

Do you have an anvil or rock collection that you want to take to collectors' meets?

We had enough for living two months in our 1300 and it weighed 1840#.

With 5 kids, the luggage can be overwhelming. I have not yet weighed the trailer in an empty condition, but from what I have read it is likely around 1500#. The capacity of the trailer is 2000#. 500# is not much cargo for seven people.
The van I will be using for a tow vehicle is a Savannah 1500. I plan to add air bags to the rear suspension, but with the seven of us it will be almost full. The cargo space is even more limited by the fact that the bench in the back of the van converts to a bed. When used as a bed, it takes up what little cargo space there was. So, the trailer is where we will carry most of the gear.

Attached is a picture from this years trip in good old #19. Behind the back bench was also loaded to the roof. The back dragged from time to time. I think we may have been a smidge overloaded.

[cpaharley2008]

Originally Posted by David Tilston

With 5 kids, the luggage can be overwhelming. I have not yet weighed the trailer in an empty condition, but from what I have read it is likely around 1500#. The capacity of the trailer is 2000#. 500# is not much cargo for seven people.
The van I will be using for a tow vehicle is a Savannah 1500. I plan to add air bags to the rear suspension, but with the seven of us it will be almost full. The cargo space is even more limited by the fact that the bench in the back of the van converts to a bed. When used as a bed, it takes up what little cargo space there was. So, the trailer is where we will carry most of the gear.

Attached is a picture from this years trip in good old #19. Behind the back bench was also loaded to the roof. The back dragged from time to time. I think we may have been a smidge overloaded.

If that vehicle is front wheel drive you were definitely overloaded.

[David Tilston]

Originally Posted by cpaharley2008

If that vehicle is front wheel drive you were definitely overloaded.

Rear wheel drive, but we were definitely overloaded. This is why we have a new to us rig.
I felt the front end kind of floating sometimes. Scared me.

[lamimartin]

Originally Posted by floyd

Seriously; do you know of a single bonafide case of someone being denied insurance or payment due to an upgrade in the frame or suspension?
I have been building cars, trailers and light trucks for 40 years including my own chassis designs, and I have never been denied coverage.
I don't know of anyone personally who has been denied coverage either, and I know many builders and hobbyists. Of course, I live in the U.S.

Hi Floyd,
There is no doubt an expert can upgrade a trailer capacity. Your plan would be the ultimate solution, but you are a rare exception if you could make it safe and economical. With a limited budget and knowledge, 1st thing to do is to check what can be made lighter.

I understand your point about insurance, but in case of failure or accident of a modified RV, are the insurance companies going to pay without checking or asking questions ? As an expert, you have all the answers, but anybody else is better to have very convincing paperwork or official inspection to back it off. Times are tough... Insurance companies are finding new questions and exclusions clauses every year. Better be safe than sorry.

[lamimartin]

Originally Posted by David Tilston

Attached is a picture from this years trip in good old #19. Behind the back bench was also loaded to the roof. The back dragged from time to time. I think we may have been a smidge overloaded.

Hi David,
2011 GMC Sierra 1500 Capabilities | Pickup Truck | GMC On GMC site, rear gross axle capacity and leaf spring capacity is the same: 3750 lbs. Adding air suspension booster does not increase your axle or tire capacity, but only helps keep your vehicle level with a heavy weight on your hitch attachment. Sudden tire or axle failure is the last thing you want with the whole family aboard.

Relocating part of the load in a RV or trailer may be a solution, but whatever gain you make on the rear suspension may be practically cancelled by the added weight applied on the hitch ball from the RV coupler which is a couple of feet behind your towing vehicle axle. Moving 500 lbs on the RV but adding 200-250 lbs from the trailer tongue is not worth the trouble. You need to move more than 500 lbs on the trailer to make it cost efficient and safe.

There is no doubt your rear suspension, and rear axle is overloaded on the picture and from your description. In order to take advantage of your 4300 lbs vehicle towing capacity, it may be a better idea to rent a high capacity cargo trailer and a tent or a bigger capacity RV that can carry ALL your equipment and luggage. At such combined weight level, you will need independent brakes on your trailer. This will add cost to your project.

In short:
Increasing Trillium cargo load capacity cost ??? Without modifications, it may not be worth the trouble. Your rear end will continue to be overloaded by adding RV tongue weight.

increase hitch capacity: definitely

Check your rear end tire rating vs load: a must

Plan for a higher load capacity cargo trailer or RV with independent brakes ?

[Byron Kinnaman]

Originally Posted by David Tilston

With 5 kids, the luggage can be overwhelming.

Not if you do it right. When our kids were still at home (3) we could fit everything we needed into the trunk of a Dodge Aries. Then everything came out was loaded on the backs of all of us. A 5 mile walk to the fist stop, with all that was needed for a week on our backs. If we could do that surely anybody can reduce the amount of stuff to a reasonable point.

[David Tilston]

The Trillium has electric brakes, and the van has a brake controller.

I am not sure what you mean by a high capacity cargo trailer. We need the trailer to sleep the kids.

I am seriously considering a totally new frame.

Is aluminum a viable option, or should I stick to steel?

[floyd]

Originally Posted by David Tilston

The Trillium has electric brakes, and the van has a brake controller.

I am not sure what you mean by a high capacity cargo trailer. We need the trailer to sleep the kids.

I am seriously considering a totally new frame.

Is aluminum a viable option, or should I stick to steel?

Stick to steel, It is much cheaper and a good aluminum welder is more difficult to find. You could have it powder coated or coated with POR15.
It will surely outlast your use for it.
Besides any future accessory would be easier to attach.

[lamimartin]

Originally Posted by David Tilston

The Trillium has electric brakes, and the van has a brake controller.
I am not sure what you mean by a high capacity cargo trailer. We need the trailer to sleep the kids.
I am seriously considering a totally new frame.
Is aluminum a viable option, or should I stick to steel?

Hi David,
I fully agree with Floyd that a new steel frame is likely the best way to safely increase RV cargo capacity at a reasonnable cost on your Trillium 4500, preserving the sleeping space for your kids. Chasing a higher cargo capacity RV, often with heavier dual axle, is likely going to end up at a weight higher than the towing capacity of your vehicle.

Upgrading your RV frame should not significantly increase RV tounge weight, so any increased cargo capacity in the RV will reduce the truck rear axle load to safer levels. A professionnal can precisely match the final weight, desired load capacity frame gauge, stronger coupler, suspension and brake capacity. Instead of net reduction of 300 lbs on the rear axle (considering tongue weight), you may quickly fall back within safe load limits on all axles (truck and RV). This exercise will require a very high level of expertise and experience to properly balance all variables, design and weld together something that will work for you.

Good luck.

[Daniel V.]

Originally Posted by David Tilston

Can this be increased? Even 2500 lb would help.

Throwing in another idea... how about asking Tom from TrilliumRV himself. He's often faced with these types of questions and I'm sure would provide valuable input, not to mention that he may actually have been involved in designing/building your trailer in 1978.

[David Tilston]

Originally Posted by Daniel V.

Throwing in another idea... how about asking Tom from TrilliumRV himself. He's often faced with these types of questions and I'm sure would provide valuable input, not to mention that he may actually have been involved in designing/building your trailer in 1978.

Sorry, total newbie, who is Tom, and how do I ask him?