Tandem towing

Randy_the_Hack · 08-01-2011, 11:56 AM

Hey - new to the forum... and I have a question. I'm needing to tow a tag-along trailer behind my 1990 T-2470 bumper pull travel trailer. What do I have to do to ensure the bumper on the TT is strong enough? I've checked the legality of tandem towing in Kentucky and it's OK as long as total combined length doesn't exceed 70'.

Just trying to figure out what I need to do to make it happen. Any help, tips, etc. would be greatly appreciated.

MACK C-85 · 08-01-2011, 01:23 PM

The bumper will NOT hold it, it is rated for less than 100lbs. You will need a frame mounted hitch and have to be careful that the weight added to the rear of the trailer doesn't create a too light tongue weight and cause sway issues.

There are several threads on here about adding a frame mount hitch.

Mack

Randy_the_Hack · 08-01-2011, 03:19 PM

Not challenging your response at all - after all, I joined this site to get some answers on this subject from people who are in the know - but is this documented somewhere? I've asked the same question in other locations and I've heard 500 lb limit to no limit to no weight at all... which makes me wonder why companies like Curt even make such products to facilitate such features, let alone where I can turn to find this information documented?

It sounds like this isn't something I should do. Guess I need to figure out something else...

MACK C-85 · 08-01-2011, 03:47 PM

On my Sunline the weight limit is posted on the back of my trailer.It's also mentioned in the manual. We've had several instances on the site of the spare breaking the welds.

As far as the tongue weight, it's a simple lever, any weight carried on the rear of the trailer will lever over the axles and lift the front of the trailer.

It can be done, but you have to be careful with the weight distribution.

Mack

Steve Collins · 08-01-2011, 03:49 PM

IIRC, there was a tag on our bumper when we got the trailer that stated 100# weight limit. I spoke with the dealership about it and they confirmed it.

A close examination of the welds holding the mounting stubs to the bumper pretty much confirmed to me that weight limit. It was as much the absence of some welds that really stood out.

Good enough for me.

If you want to do this, have a receiver style hitch welded/bolted directly to the frame in at least two places and preferably four. By using a standard 2x2 receiver, you can then use things like bike racks, etc. that all fit in those receivers. Skip any connections to the bumper.

mainah · 08-01-2011, 04:31 PM

There have been some posts of bumpers falling off! Not a good thing while towing a trailer. Frame hitch is the way to go.

**Sunline Fan** · 08-01-2011, 07:14 PM

I don't believe a 1990 would have a sticker saying that the bumpers are rated for 100 lbs, but I have no reason to believe that the rating would be any different from the later units that had stickers. Sunline seemed to make these bumpers weak to discourage people from putting a lot of weight on them. Adding a few bikes back there and who knows what else can drastically change the weight balance of the trailer and make it much more miserable to tow.

While a number of states do permit tandem towing of a bumper pull trailer behind a fifth wheel, very few states permit tandem bumper pull towing. So this really hasn't come up in the past. The only reason most people have mounted a hitch back there is to put a hitch mount bike rack on that they can also use with the tow vehicle.

Some RV dealers do have a kit available that includes a hitch tube and bumper mount bolts. This should not be used for a trailer at all, and really not on a Sunline even for bike racks. On that same note, many dealers also have kits for complete weld-on hitches for trailers. The frame is just much wider than a vehicle hitch and has no specific brackets. You may want to look into that unless you know a local hitch shop that can rig something up. It would weld on to the bottom of the frame rails and would be below your bumper, so it wouldn't have to move. I suppose if they want to add a brace between the bumper and hitch, that would be fine, but the majority of the weight should be carried by the welds between the hitch and frame rails.

EMD_Driver · 08-02-2011, 10:10 AM

Hey Randy... Welcome to the club!

From what I read above, it sounds like you might be confusing the weight capacity of the bumper with the weight capacity of a frame mounted hitch.

The bumper itself can barely hold a spare tire. A frame mounted hitch would be good for it's rated capacities.

As stated above, ANY weight on the frame mounted hitch will reduce the tongue weight of the trailer. You must be sure to maintain 10-15% of the travel trailer's weight on the hitch of the truck. If not, your rig would be an accident waiting to happen.