Hi all. I'm designing a custom aluminum gooseneck trailer (19 feet) to be used as an RV.

I'm trying to figure out placement of my water tanks. Two questions:

1) Where should the most weight be placed-- in the front of the trailer or over the axles?

Advice for trailers generally seems to be that the most weight should be placed in front of the axles. But I've come across a few people in forums who say goosenecks are different and the most weight should be placed directly over the axles.

2) How important is it to have the weight distributed evenly side to side? It would be ideal to have my tanks on the left side in terms of the floor plan I've gotten worked out. Will this be ok or will it make my life hell when towing?

Thanks for any input!!

 

I would have the tanks centered if it were me and closer to the front axle of the trailer., if you do a rear bathroom then that would balance a tank on the front axle perfectly.


Most of a gooseneck's load needs to be on the trailer because the king pin wt gets heavy very easy..or should I say the amount on the ball.

 

Thanks, senix. By "most of a gooseneck's load needs to be on the trailer" do you mean on the axles?

 

certainly, the heaviest portion does.

 

It is going to be near impossible to figure out a rough guess as to what the weight distribution of the finished product will be. If you had a way to figure out the build materials weight and everything you are installing you may be able to get some approximation, but I wouldn't think that would be even close to accurate in the end. It may give you some sort of direction, however.

Any weight that will vary greatly (like liquid levels in tanks) should be somewhere that won't affect the weight on the tow vehicle much. If you have tanks entirely in front of the axles, for example, then full tanks are going to transfer a lot of weight to the tow vehicle. On the other hand, tanks behind the axles will add weight to the trailer, yes, but that weight distribution will be subtracted from the tow vehicle. So not only are you adding the weight of the liquid but the transfer it causes adds the weight taken off the hitch/pin/ball.

If your whole trailer is 19ft long that is a pretty short trailer. I don't think weight is going to be much of an issue with anything over a 3/4 ton truck. The higher the gross weight (fully loaded trailer) is and the lighter the capacity of the tow vehicle is the more weight transfer is going to matter.

20-25% of gross weight on the hitch is a good target. With as small of a trailer as that is you should have no problem with this. However, try to stay under the GVWR of the tow vehicle with the loaded trailer hooked up (weigh the truck, weigh the load on the rear axle, then subtract the weight of the truck from gross to give you remaining payload, then look at the rear axle rating. Likely your rear axle weight subtracted from your rear axle rating will be higher than the remaining payload, but just make sure. Your best to stay under the total GVWR, but that aside you never want to exceed the rear axle rating, and tire capacity on that axle = bigger safety issue than exceeding gross).