trailer tandem axle allignment

[ready4lake]

I think I have an allignment issue with my trailer. At the end of the season last year my trailer started falling apart. The fenders cracked around the mounting bolts and the lights would even come loose. The trailer still pulls smooth and tracks fine. I just dont know what would cause it to vibrate enough to cause this. The tires are wearing in an extremely uneven pattern. Is my axle allignment off or could it just be as simple as new bearings? The guy I bought the boat from said he had moved the axles back a little to distribute the weight of the boat properly. I would like to have it ready for this season soon.

 

[ready4lake]

Re: trailer tandem axle allignment

To add, I did not think moving the axles was possible without cutting and welding new mounting points and it doesn't look like that has been done.

 

[90stingray]

Well... you will have to physically look at the axles to determine how they were moved. Could be movable by bolts, we don't know... you need to look or take pictures for us to look and see. You can use a tape measure to check the alignment of the axles. Since your tires are worn funny now, I would get new (after you fix problem of course) Also, check bearings for tightness, wear, and reservice them.

Sent from my DROIDX using Tapatalk

 

[ready4lake]

Re: trailer tandem axle allignment

I am going try to take pics tonight. If I can get some good pics, I will post them tomorrow.

 

[bruceb58]

Re: trailer tandem axle allignment

You need to do some measurements. First thing I would do is measure from center of spindle to center of spindle on each side of the trailer. Take the bearing protector off to do this measurement I would then measure from tip of tounge to center of forward spindle on each side.

What the previous description doesn't measure is if the toe isn't correct. For that measurement, you need to measure from rim to rim on the front and back of the wheels on each axle.

Inspect the bushings where the springs attach. Very worn bushings can throw alignment off.

 

[UncleWillie]

Re: trailer tandem axle allignment

I would consider that the cause and effect may be reversed.

The trailer isn't killiing the tires, the tires are killing the trailer.
Mis-alignment will wear one edge of the tire or the other, usually evenly.

Uneven wear could be due to a tire failure internally, or unbalanced tires.
Once uneven wear becomes even noticable, it is too late to control it.
It will only get worse and shake everything to death.

It is time for new tires, and have them balanced!

Does your trailer have shocks? Are they good?
Should you add shocks? They are not expensive, cheaper than tires!

 

[ready4lake]

Re: trailer tandem axle allignment

I will take all the measurements tonight when I get home and have them posted along with pics. I do think the tires may be bad because it is a wear pattern that I have never seen before. This is just the first tandem axle trailer I have owned, and I am not familiar with them. I am going to have to replace them anyway, so what tires do you recommend? The boat weighs somewhere around 4k lbs.
I do not have shocks on my trailer.

 

[bruceb58]

Re: trailer tandem axle allignment

I would normally agree with UncleWille but since you stated the the original owner moved the axles, I would definitely double check this so that the next set of tires don't get ruined.

 

[ready4lake]

Re: trailer tandem axle allignment

Well I did a little measuring and the spindles are 33" on both sides(center to center). Could not get any good measurements for toe position since I didnt have help and it was dark. I did however get a couple crappy pics I will upload.

 

[ready4lake]

Re: trailer tandem axle allignment

I will post the pics soon, I am having trouble uploading from my phone.
I did also find that you can move the axles on this trailer. They are attached to the trailer frame with u bolts.

 

[ready4lake]

Re: trailer tandem axle allignment

Well here is a pic of the u bolt that attaches the crossbeam to the frame. There are four all together. I know its not the greatest pic but I will have to wait till after work today to get some better shots. Shouldn't the u bolt be the other way? I am an aircraft mechanic and we practice always facing the threads up or forward. This seems kind of unsafe to me.

Here is one of the tire. It is hard to tell but it is almost like there is a shelf or steep drop off from one tread line to the next. Could just be camber, but there are also waves in it all the way around which you cannot see in the picture.

Those are the only pictures I can give you until later today. Like I said it was dark and a flashlight and "smartphone" just couldn't get good pictures.

 

[ready4lake]

Re: trailer tandem axle allignment

I also looked at the bushings on the leafsprings and the equalizers. They did not seem to have any play, but I would have to take them apart to do any further inspection since view of the bushings was limited.

 

[bruceb58]

Re: trailer tandem axle allignment

Its ok for those u-bolts to be down.

 

[ready4lake]

Re: trailer tandem axle allignment

Ok, thanks I was not sure about the u bolts. Does the tread wear look like normal camber wear for a trailer? I am going to jack up the trailer after work and do a more in depth inspection. I am hoping it's just bearings. As far as the axles being alligned with each other, I am good right? Both spindle measurements from center to center were the same. I will do some more measuring to make sure they are in allignment with the trailer, but I'm sure they are because the trailer tracks straight.

 

[bruceb58]

Re: trailer tandem axle allignment

What accuracy are you meauring to? They have to be exact meaning within 1/16 or 1/32 of an inch.

Are all the tires worn in the same way as that one and in the same direction?

 

[a1nowell]

Re: trailer tandem axle allignment

From your picture it looked like the outer edges of the tire were wearing faster than the center. If so that is an indication of under inflation.

 

[bruceb58]

Re: trailer tandem axle allignment

Looks to me like only one of the outer edges is wearing more. Might want a better picture.

 

[LilRedNeckGirl]

Re: trailer tandem axle allignment

before yo go moving axles, guessing at everything under the trailer and such, take it in and have the axles aligned. they do it just like a car or truck, @ camber and toe. a twin axle should run around 100 bucks, give or take, and knowing what the alignment was will give you a good solid place to start. you cant accuratly check alignment by measuring with a tape measure.

 

[ready4lake]

Re: trailer tandem axle allignment

I did some more measuring and I am convinced that the axles are straight. I then jacked up the trailer and found that my bearing were wore out on 3 of the 4 wheels. So I am going to be replacing the bearings and do an overall inspection of all the parts when I have it torn apart.