Dexter Axle Over-Under Conversion Kit

[Sunline Fan]

Hi Everyone,

For those of you who always ask about the Over-Under conversion, here's some pics to show a job completed. I can't help as to why you can't just put the axles under the spring, but this is what a complete setup from Dexter looks like. If you have any questions or want a detailed pic of something, the trailer is home right now, so I can go take pics tomorrow.

Here's a little background info. The trailer was originally covered by my dad (he designed and built the whole cover) and designed to fit in a 7' garage door. Since the conversion, it wouldn't fit and dropping the air out of the tires didn't work. That's why you see these small wheels on here- they're just for storage. In order to (safely) take the trailer on the road, the wheels and tires must be changed out with stock size 15x7 rims and ST205/75/R15C Goodyear Marathon's.

Here's the trailer just after it came out of the garage:



Close up of small wheel:


Extended Equalizer and spring bolts with grease zerks (added at time of conversion, along with new bushings)


Here's some close up's:





Here's some farther away shots showing the height difference. As you can see, the casters on the back were very important at the stock height. Now, they rarely hit, if ever.



I thought about putting a tape measure from the ground to the frame to show the difference, but I thought about that after I had the wheels installed and jack put away. I wasn't about to pull it off just for a pic.

For those of you who noticed, I did hook up the chains before hitting the road.

Also, sorry for it being so dirty. That's why I brought it home, was to wash it . It sat outside while one of the cars had to be worked on, so that's how it was dirty.

Another thing, for those of you following, this was the first time I towed a trailer with electric brakes with my Ex. Towed great and brake controller worked great, though I'll admit the trailer was empty!

Jon

[JohnB]

Jon

Thanks for the pics. To add to your set, here is the Dexter axle before the kit was installed on my TT so folks can see what it looks like before the kit.



Jon, question:

Did you Dad add that 3/8 or 1/2" bolt screwed into the all thread rod coupling to help the axle for rotating with the kit added? Or did that come with the kit?

PS. Your dad is very handy and creative with that trailer.

Thanks

[JohnB]

Originally Posted by Sunline Fan

Hi Everyone,

Snipp..

I can't help as to why you can't just put the axles under the spring, but this is what a complete setup from Dexter looks like.


Jon

Jon compare these 2 pics.


What Dexter did looks very right by adding that top saddle on. What do you mean "what can't you just put the axles under the spring"

Can't figure out what you are up to.

Thanks

John

[Sunline Fan]

John,

I just asked him and he said that part came with the kit. He also mentioned he welded both brackets on there. He thought they didn't need to be, but it's better to weld it than just rely on a little bolt.

Jon

[Sunline Fan]

John,

I was asked a long time ago about why the axles just couldn't be put under the springs. I didn't have the pics and hadn't looked that closely at the whole thing in a long time, so I couldn't remember, but there was a reason.

I guess it could be put under the the spring if the one spacer wasn't welded on. Just put the spacer on top and set the whole thing up upside down. The theory is there, but there is some reason why it can't work like that.

I was hoping that whoever asked that could see these pics and it would answer their question.

Jon

[pats-fan]

The top saddle is needed to keep the axle from rotating when the brakes are applied. The drop in the axle needs to be in the same position as it was when the axle was on top of the spring for the magnet and brake shoes to work correctly.
I Have pictures of my sunline at different stages of the axle flip, But can not figure out how to post.
I did not use the dexter conversion kit. I found saddles and welded them on top parallel to the ones on the bottom.

[JohnB]

Pats-fan

I fully agree we need the top saddle or the spring pack will rotate on the axle.

To post a pic. First you have to have your pic's on a photo-hosting site of some type that is open to public access. Then they are basically linked to this site.

Try to keep your pics to 640 x 480 pixels. If you make them wider then that it scrolls the entire page. Also try to keep the size do less than 100 meg. 50 meg works great.

See this how to link.How to post pic on Sunline Club

If you have any problems, let us know. Glad to help and glad to se the pics.

IS the kit from Dexter just the top saddle?

John

[pats-fan]

The Dexter kit includes the saddle with studs built in to allow you to secure it to the bottom saddle, the purpose is to eliminate welding. However what changed my mind to go with the welded saddle, is the instructions with the Dexter kit recommends welding the new saddle so why not just go with a welded saddle??

[Al in PA]

I need a little clarification. My T-2553 goes to the dealer for the axle flip next Monday and I want to have it done correctly. I understand John's statement that the welded saddle would keep the spring pack from rotating under the stress of braking. Therefore, I understand Pats-Fan's decision to have two welded saddles in parallel. Pats-Fan. I do not understand your comment about the effect of the axle position on the proper functioning of the electric brakes unless you are referring to diminished efficiency in the event of spring rotation on the axle. I guess the bottom line is that the Dexter kit should be welded and parallel saddles should be welded in place also: Is this correct?

[pats-fan]

Al
I do not think you have to weld the dexter kit, but they do recomend welding. My point is if you are going to weld the saddles from the kit, why not just weld the saddles, that are less than half the price of the kit.
As for the brakes, I thought you was saying to just flip the axle and use the existing saddle, in that case the brakes would not work.

You will like the way the trailer tows after you have the axles flipped. When it is being done, the suspension has to come apart, adding the Dexter heavy duty kit or EZ-flex, should only be the price of the parts.

Do not forget about the hitch height, make sure the drop bar will work with the change in height.

[Al in PA]

Pats-fan,
Thanks for the response. I ordered the Dexter flip kit. Is the Dexter heavy duty kit part of the flip kit or should I add that to the work order? My reason for installing the kit is two-fold: (1) The back drags pulling out of the driveway and (2) I plan to store the trailer in my barn in the winter, but I don't think I'll get up the bank incline without additional clearance. I have no problem with its towing characteristics. If it tows better, that's like icing on the cake. I already talked to the service manager about changing the hitch height. Thanks for the suggestion. Just out of curiosity, how much does the hitch height change?

[Sunline Fan]

Al,

I think ours had to raise about 3-4 holes on the drop bar. I just pulled that trailer for 4 hours today on the highway and it tracked perfectly. The only time I went off onto the rumble strips was when I was passing a 5th wheel on a hill. I slowed down some and he kept the same speed if not sped up. I think the draft is what pushed me over the line. Whenever I pass a fellow RVer/trailerer, I like to move over in the lane as much as possible to eliminate that pull as much as possible.

I think the mileage could have been a little better with the trailer at stock height (not as much sticking above the TV), but I don't think it would be a large difference. I got 10.6 going about 70-72 on my speedo, which was about 65-68 on a cop's watch. Farther up north when it got more open and traffic sped up all together, I kicked it up to about 75 for most of the time, and it did fine. The mileage had been about 11.2-11.3 when I was going slower, but the total trip mileage was 10.6.

Jon

[Mark]

Please don't take this the wrong way, but do you think it is wise to tow at those speeds? I know you have probably done your homework, so I assume you know your what tires are rated for, but why the "need for speed".

A small emergency maneuver at 55 MPH is heard enough, let alone 10 MOH more?

Just curious?

[Tracykerr]

I flipped the axle on my 1991 Sunline 16ft camper and i didnt buy even a washer . i just unhooked it flipped it over and put the ubolts back on . the flat plate welded to the axle is now under the leaf springs with the u bolt pointed up. I realise the axle is upside down and that the brakes wont work but they didnt work when i bought it and never have worked . i pull it with a 2005 GMC Sierra 2500 with air bag suspension + the factory leaf springs and my truck has a 6 inch lift kit on it and i dont have any problem stopping , it does fine with just the truck brakes only. it raised the camper up probably id say at least a foot maybe more ..so much so that before i used a 11inch drop hitch and it still was lower in the back of the camper than at the hitch . now i use a reciever hitch that comes straight out ...zero drop ...and the camper sits level . Now its pretty top heavy it rocks side to side if you go faster than 65 and if you turn into someplace with a curb ...forget about it ...it rocks so far over that it throws everything that aint nailed down all over hell , the inside of the camper looks like king kong picked it upand shook it .lol myplan is to get some 15in wheels and put 31x10.50x15 tires on it and either take it to KC Spring and have them beef up the leafs or add a couple more or put airbags between the frame of the camper and the axle. I understand that a flip kit would be simpler , cheaper and more stable BUT the camper now sits the same height as my truck with 6in lift and 35's on it and thats with 14'' rims and 205/75/R14. it looks pretty tough even with the little tires and wheels .Once i get the wider tires on it and beef up the suspension on the camper i think itll do fine . if you need to go faster than 65 pulling a camper maybe you should leave sooner LOL.

[264SRinPA]

You can't just flip the axle upside down. The axle has a camber built into it. That could be part of your problem of the rocking side to side. And you are probably going to get a lot of tire wear. As for the brakes not working, you wouldn't pass inspection in Pa. If you ever get into a bad sway situation, you won't be able to correct it without trailer brakes. If you can't comfortably drive above 65
then you have a bad setup. Not that I would ever do it, but I could tow our trailer just as comfortably at 90 as it does at 65.

[JohnB]

Hi Tracey,

I'll try to be helpful here before something happens.

Doing an upside-down drop axle setup creates some issues, as you have found out.

As 264SRinPA stated, the wheel camber is in the axle itself. The center of the axle is bent "up" (positive Camber), so when the camper is loaded, and the weight presses down on the axle seats (the plate that is welded to the axle tube that holds the spring), the axle tube will start to flatten out as the weight is added. Normally, the axle tube does not go dead straight (0 camber) and stays above the center to allow a positive camber at the wheel.

You now have a negative camber to start with, which will get even more negative as the weight of the camper and any cargo is added. The wheel chamber is off a lot. This will likely wear tires badly, being very negative on the camber.

The axle spindles are also welded into the tube to create a wheel toe angle. They know which direction is forward and can be welded in to create a slight tow-in angle so that the wheels will spread closer to the 0-toe angle going down the road. If you tow the axle backside forward, you may have an excessive tow-out angle, which will wear the tires badly.

Your thrust angle may also be way off. The distance from the tow ball to each wheel on both sides of the camp should be within +/—1/16" so the trailer tracks straight. The axle being up that high can magnify the thrust angle to be out of whack. The end result is the trailer can track to one side or the other going down the road, plus wear tires.

Springs: if your springs are originally from 1991, that is 33 years old, with the amount of excess spring travel there is now, metal fatigue from 33 years with added large flexing, which is jolting the camper all over, can crack a spring. If the main leaf cracks through on a single-axle trailer with a drop axle downside up to be a lift axle, the camper frame will drop a lot, until something stops the camper from going lower. This could be a really bad day camping if it happens on the highway. It is also not good practice to reuse U bolts. If they have been in use for 33 years, it is not good to reuse them.

Brakes: some states allow a certain weight to be towed with no brakes. Pending the states, some are 1,000#, 2,000#, and maybe very few, 2,500 to 3,000#. I am not sure what your state allows, check and see.

There is, however, a federal requirement that a trailer that was fitted with brakes (Sunline did) must have a working emergency breakaway system to activate the brakes and hold for up to 15 minutes upon decoupling of the trailer. See the Code of Federal Regulations here. https://www.ecfr.gov/current/title-4...section-393.43

Your spring shop will see your setup and may refuse to work on it until it comes into compliance or they are hired to make it compliant.

This may help you. They now make off-road campers that are way up in the air. This may not be in your price range, but it may solve the problem if you want your camper that high up. Curt Manufacturing, now owned by Lippert, makes a Street mode to Beast mode suspension with brakes.

Here is a U tube on them

https://www.youtube.com/watch?v=bT3JIGSsNzk

I'm not sure if they will sell it as an upgrade, but other companies are now doing Independent Trailer Suspension; try a search on them. It seems these high-lift setups fit the off-road group.

I hope this helps,

John