Single Axle to Tandem Axle Trailer Conversion

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08-15-2013, 09:39 PM
walb0244

Single Axle to Tandem Axle Trailer Conversion

I want to get your guys opinions on this idea. I have been trying for awhile to find a tandem axle trailer to switch for my single axle but didn't come up with any luck on that. So the other day I ran across what I thought was a good deal on Craigslist. So I found a tandem axle trailer for a 2008 Ranger boat trailer. The guy was parting it out. The frame forward of the axles was all bent due to a wreck. The axles were torsion flex axles, one with hydraulic disc brakes, and they also have oil bath bearings. Well I was able to pick up both axles with 5 tires and rims and the spare tire mount for $500. So I'm going to be trying to convert my trailer from single axle to tandem. Can anyone give any ideas of things that I should make sure of before I attack this project?
08-16-2013, 09:05 AM
kaneboats

Yea, check the garage fridge and make sure it's filled to capacity.
08-16-2013, 10:56 AM
cornrickey

my axles are bent down in the middle to allow the boat to clear. I'd make sure the new axles will do the same and are the proper width.
08-16-2013, 11:40 AM
aerolland

I'd be interested in the left over single axle and wheels. Spring or torsion? What wheels did you have?
08-17-2013, 08:46 PM
z28ke

Single Axle to Tandem Axle Trailer Conversion

Quote:

Originally Posted by kaneboats

Yea, check the garage fridge and make sure it's filled to capacity.

Yea I was thinking the same. Seems like a tough conversion unless you are a skilled welder/fabricator.
08-19-2013, 01:49 PM
N2OGTO

If it were me doing the conversion. I'd find a spot to drop the boat in the water for the weekend and make sure you have everything you need to get it done in a weekend. I'm interested to see your finished product. What are you going to do for fenders?
08-19-2013, 10:14 PM
walb0244

I'm trying to find a place to be able to keep it for the weekend and have everything ready to rock and roll. Is there anybody on here that has a 2006 Moomba Mobius LSV with a tandem axle boat mate trailer that would be willing to take some measurements and pictures for me? i would really appreciate it. I would like to get measurements on axle location as well as the bunk mount locations so I know how everythin should go. Also would like measurements for the fenders as well.

On fenders. I tried contacting Boatmate to get fenders from them but the lady I talked to did me no good at all. I told her I wanted tandem axle fenders for a project where I was converting my single axle trailer to tandem axle. She wanted to know my Trailer Vin number so that she could order the correct fenders. I tried to explain to her that i didn't want the same fenders. She finally told me that she would have to get me to someone that had more knowledge. I have yet to hear back from her.
08-19-2013, 10:34 PM
walb0244

Quote:

Originally Posted by aerolland

I'd be interested in the left over single axle and wheels. Spring or torsion? What wheels did you have?

The axle is a torsion axle.

These are what my Rims looks like. I grabbed this picture from Google. I have two that are chrome and my spare is white. The two tires on the axles are fairly new. One bought last season and one bought about a week ago.
http://t1.gstatic.com/images?q=tbn:A...rXgYPanwJ__LzE
08-22-2013, 10:10 PM
walb0244

Nobody is able to take some measurements for me? I would really appreciate it.
08-23-2013, 07:23 AM
aerolland

Quote:

Originally Posted by walb0244

Nobody is able to take some measurements for me? I would really appreciate it.

Check your inbox when you get a chance.
08-23-2013, 02:56 PM
cab13367

Quote:

Originally Posted by walb0244

Nobody is able to take some measurements for me? I would really appreciate it.

I've got an 06 double axle. Let me know what measurements you need and I will try to get them this weekend. Keep in mind though that my boat is on the trailer so that may limit what I can measure as far as side to side measurements. Email me what you need - [email protected]
08-23-2013, 05:22 PM
WFO

Make sure that you get your tongue weight correct. If you don't the trailer will pull like crap or even be dangerous. I think Boatmate puts 7% of total package weight (Boat and Trailer Combined) on the tongue. You can get it close by centering the tandems on the old axle centerline but, I'm guessing that you'll have to push the axles back a few inches to load the tongue correctly. I recommend tying the two axles together as a unit at the desired spacing with a piece of square tube "heavy tacked welded" to both of them. Put the square tube directly under the current frame rails like a spacer between the axles and frame. Align the centerline of the tandem unit to the old centerline clamp it to the frame and measure the tongue weight. If it is too light or too heavy, un-clamp, adjust, re-clamp, and measure.

Make sure that the "tandem unit" is square and centered side-to side and make sure that every time you clamp the unit to the frame you make sure the measurement from the front of the tandem unit at the port frame rail to the front of the tongue equals the the same measurement on the starboard side. Doing this makes sure that your trailer tracks straight behind you. Once you get it right, mark your new centerlines and then determine how you want to affix them.

Good Luck! if you have any design questions, I'll be happy to help.
08-24-2013, 08:55 AM
94Boom

Are these torsion axles the short ones that bolt on a frame or full length axles similar to what you would use with a conventional leaf spring set up?
08-24-2013, 06:45 PM
walb0244

Full width torsion axles.
08-25-2013, 06:07 PM
94Boom

If it were me I would build an angle iron frame to mount the axles to and bolt them to the frame of the trailer to make them adjustable in case you miss the placement of the axles. If you are interested in doing this I can walk you through it. Today I removed my dads boat from the water for the season, his lift is giving him grief, and after towing his 19ft deck boat I remembered how crappy his trailer pulls. It needs more tongue weight, my dad says to me "so that's not normal?" At every bounce it was clunking on the ball.

Brian
09-08-2014, 03:02 AM
walb0244

Well since I'm away. My father-n-law is about to start the project of switching over my trailer to a tandem axle. I think I have all the measurements that I will need to be able to get this done. He is calling boatmate trailers today to get the fenders ordered. Figured this would be a good time to take care of this project before putting the boat away for the winter. He is suppose to send me pictures as the project goes along. I'll put them up on here so you guys can check it out. I'll definately be happy to have this done. Just last week the trailer blew a tire and left my wife and son on the side of the road for awhile. Atleast with tandem axles she could have gotten to a better spot to be able to get the tire changed. I do appreciate all the help that I have gotten from the guys on here. Especially Al.
09-09-2014, 09:27 PM
ninedriver

Definitely keep us updated. Thanks.
09-10-2014, 09:50 AM
walb0244

2 Attachment(s)

Attachment 20843 Attachment 20844

Making some progress. Got the fenders and steps cut off. Got the new fenders, inside carpet pad, and the rubber non-slip pads ordered. Hopefully they ship out pretty soon. Will post updates as soon as I have any.
09-12-2014, 02:23 AM
walb0244

Attachment 20845

Got the axle assembly under the trailer and bolted in place. So if you remove 10 bolts and disconnect the brake line the entire assembly can be removed from the trailer. Currently says that the trailer sets nose heavy without the boat on it but he can move it by himself with one hand so it seems to be balanced. Still have to bleed the brakes and then go and pick the boat up for fender placement. Not sure how much the boat will flex the axles. The fenders were ordered from Boatmateparts.com and should arrive today. Pretty excited. Can't wait to see the end results. Hate that I was gone during the entire deal tho. I have been waiting for awhile for this project and can't wait for it to be done.
09-14-2014, 05:43 AM
walb0244

1 Attachment(s)

Attachment 20846

Got the boat back on the trailer. Says it towed great. Needed the boat back on the trailer so could install the fenders. Have sense ran into some problems but hopefully can figure out how to fix the issues and continue on.
10-10-2014, 09:08 AM
walb0244

1 Attachment(s)

Attachment 20972

Project is complete.
10-10-2014, 11:02 AM
sivs1

1 Attachment(s)

Looks great, how does it pull? Here is my boatmate tandem trailer, can't tell them apart.
10-10-2014, 01:37 PM
deerfield

So, what is the attraction to haul a boat to a winter ski resort?

Quote:

Originally Posted by sivs1

Looks great, how does it pull? Here is my boatmate tandem trailer, can't tell them apart.
10-10-2014, 01:56 PM
sivs1

Quote:

Originally Posted by deerfield

So, what is the attraction to haul a boat to a winter ski resort?

it's 10 minutes from my house, we were on the water later that day. At 7,000 feet we have a short season and have to use any day above 50!
10-11-2014, 05:08 AM
walb0244

I have not gotten to see the trailer in person or pull it yet. I won't be able to do that until around March time frame. But my father-n-law who did the work says he towed it at 60ish and it towed great. There are some differences between what it should look like and what it does look like. I'm not gonna complain too much since it was all done for me. We ordered the fenders from BoatMate. They only thing that isn't a BoatMate trailer part are the 2 axles that are under it. I got them from a fishing boat.