I have a 1900 Pro - V IFS which is pulled on a dual axle Shorelander trailer. I'm pulling the boat and trailer with a 2007 Expedition. When driving down the road under 60 MPH I can't even feel the boat and trailer behind me. The minute I exceed 60 MPH there is a terrible vibration throughout my truck and I would assume the trialer too. So bad that I have to keep it under 60. No apparent difference with the cover on or off of the boat while driving. No tire wobble or any apparent issue with the truck, trailer or boat while having my brother driving behind me. The only thing I can come up with is that on the port side of the boat the axle is approx. .50" - .75" closer to the back/end of the actual trailer. Or the draft off of my truck and across the boat is an issue at the higher speeds. Oh, and no obvious abnormal tire wear on any of the four tires. Air pressure and bearings are ok. It would be nice to drive 60 to 70 MPH on the thruway especially when going long distances. Any ideas on how to correct this? Thanks.

Do you notice this with out the trailer?? Sorry but gotta ask.

No! Good question, had my truck completely checked out and it is fine. I'm really stumped on this. BTW, I pulled an Explorer for a year prior to the Pro - V with the same truck but on a single axle Eagle trailer, No issue above 60 MPH.

The fact that the axles don't appear to be square with the frame (by the 1/2-3/4" you mentioned) should definitely be addressed. It may not be causing the vibration, but it will probably start wearing the tires badly. Anyh idea what tongue weight your rig is set at? If not heavy enough, and considering the possibility of "up-lift" caused by the wind pressure against the hull, it may be getting loose on the ball. Maybe throw some sandbags in the bow, and see what happens with more weight on the ball.
HRG

speaking of tounge wieght is your reciecer have an upright angle or does it come flat? Maybe if you have it angle down that will put more wieght towards the truck and bring the front of the boat and trailer lower. Not sure but i had this issue with my atv trailer when i had the reciever angle up instead of down.

Could be a trailer wheel that's badly out of balance. But Do not totally rule out the truck just yet. You could have a bad driveshaft universal joint that only makes itself known under the increased load of towing the trailer.

Any chance you have a buddy with a rig that is close to the same weight as yours,you could hook up and tow, for a test? Could quickly eliminate truck or trailer.

have all the tires on the trailer balanced. Might be one out of balance or even a shifted belt. They will be able to tell when they balance them if there is an issue

The fact that the axles don't appear to be square with the frame (by the 1/2-3/4" you mentioned) should definitely be addressed. It may not be causing the vibration, but it will probably start wearing the tires badly. Anyh idea what tongue weight your rig is set at? If not heavy enough, and considering the possibility of "up-lift" caused by the wind pressure against the hull, it may be getting loose on the ball. Maybe throw some sandbags in the bow, and see what happens with more weight on the ball.
HRG

I definitely plan to have the axles squared up before the season, with such a wide trailer that could very well be part of the issue because it is exagerated across that width. Addtionally I plan to have all four wheels balanced too. Have no idea what the tongue weight is and you make a very good point that I may be getting up lift. Dumb question, how do I check tongue weight and is there a rule of thumb as to what the TW should be? Thanks.

speaking of tounge wieght is your reciecer have an upright angle or does it come flat? Maybe if you have it angle down that will put more wieght towards the truck and bring the front of the boat and trailer lower. Not sure but i had this issue with my atv trailer when i had the reciever angle up instead of down.

My receiver pretty much is flat with the tralier, if anything it may need to come up just a little. I thought about lowering it but was concerned that I would get excessive wheel wear on the front two trailer tires and less on the back two.

Could be a trailer wheel that's badly out of balance. But Do not totally rule out the truck just yet. You could have a bad driveshaft universal joint that only makes itself known under the increased load of towing the trailer.

Any chance you have a buddy with a rig that is close to the same weight as yours,you could hook up and tow, for a test? Could quickly eliminate truck or trailer.

Never thoguht to have my brother tow the boat with his pick-up to see if he experiences the same vibration.

Dumb question, how do I check tongue weight and is there a rule of thumb as to what the TW should be? Thanks.

First of all, no dumb questions. Only dumb answers! The rule of thumb for boat trailers is that roughly 6-8% of the total weight should be on the ball, so you're probably looking at somewhere near 300#. I simply use a bathroom scale, with a jack stand from the ball socket to the scale. When you check it, try to match the height of the ball while it's on your truck, too high tends to lighten the weight, too low tends to increase it.
HRG

First of all, no dumb questions. Only dumb answers! The rule of thumb for boat trailers is that roughly 6-8% of the total weight should be on the ball, so you're probably looking at somewhere near 300#. I simply use a bathroom scale, with a jack stand from the ball socket to the scale. When you check it, try to match the height of the ball while it's on your truck, too high tends to lighten the weight, too low tends to increase it.
HRG


Well now I Know, I'll have to try that when I pull it out of storage in April. Thank you for the advise.

Ron

By chance does this vibration occur when the truck is in OD? See if it happens in 3rd gear.

By chance does this vibration occur when the truck is in OD? See if it happens in 3rd gear.

I see your point,the Engine could be lugging in overdrive. However,that would probably happen at a much lower speed than 60MPH and any vibration from it should actually disappear as the speed and RPM increased.

I don't think it has been in OD at all??? I will have to to try it in 3rd gear too and let you guys know.

I would put money on the tires being out of balance. I had new tires put on my gmc yukon. Paid for the balance and alignment. Hit the road for vacation. Everything was fine until I hit 70. At 71 the steering wheel shake made me crazy. On vacation I put the wife and kids in the pool and found the nearest goodyear shop. Brand new tires just balanced were NOT balanced. Goodyear does a "road pressure balance" (?). They balance the tires with simulated road pressure and mount the tires on the rims according to rim weight and tire weight then balance the tires. Cost
me $50.00 and 2 hours of my vacation but really improved the ride.

Have the trailer tires checked by someone who knows tires not the corner shop.

That is exactly waht I experience the minute I go 1 MPH over 60. I'll take your advise and others by gettign the wheels balanced by someone who knows what they are doing. Thank you.

Ron

I have a 1900 Pro - V IFS which is pulled on a dual axle Shorelander trailer. I'm pulling the boat and trailer with a 2007 Expedition. When driving down the road under 60 MPH I can't even feel the boat and trailer behind me. The minute I exceed 60 MPH there is a terrible vibration throughout my truck and I would assume the trialer too. So bad that I have to keep it under 60. No apparent difference with the cover on or off of the boat while driving. No tire wobble or any apparent issue with the truck, trailer or boat while having my brother driving behind me. The only thing I can come up with is that on the port side of the boat the axle is approx. .50" - .75" closer to the back/end of the actual trailer. Or the draft off of my truck and across the boat is an issue at the higher speeds. Oh, and no obvious abnormal tire wear on any of the four tires. Air pressure and bearings are ok. It would be nice to drive 60 to 70 MPH on the thruway especially when going long distances. Any ideas on how to correct this? Thanks.

balance the tires on trailer just like car or truck or broken cored in tire like car or truck with bad tire

Make sure your wheels (not tires) are perfectly round. I had a similar vibration problem and it was an out of round wheel.

Also check your ujoints and drive shaft. A bent driveshaft, or worn ujoint can cause bad vibrations at a range of speeds. Most likely its a tire out of balance, but it never hurts to look beyond the obvious.

As soon as things thaw out around here so that I can get the boat out of storage, I intend to get the wheels checked along with the axles on the trailer. I never did get it done last spring, got too busy.

CSH,
1. Check your trailer for a bad wheel.
Trailer wheels don't have to meet the same specifications as car or truck wheels. Trailer wheels can have a considerable run out or bend and still be legal to sell and use on a trailer. But, just because they are legal does not mean that they will work well.

2. Take and jack up each side of your trailer, one side at a time.

When the trailer wheel is jacked up, use a dial caliper or similar to first check the run out of the wheel. Basically, you can make your own dial caliper run out indicator by the use of a simple block, a vertical rod or bar and a horizontal rod or bar that is attached to it.
Simply adjust the height of the horizontal bar so that it is at the level of the largest part of the wheel - not the tire. Then adjust the indicator side to side, so that the horizontal indicator is close but not quite touching the trailer wheel. Now, very slowly, rotate the tire, while checking for run out, or side to side movement of the wheel. There should be next to no run out or bend on the trailer wheel.

3. Now, do the same thing for the tire. i.e. move the side to side indicator to the level and positon to monitor the center of the fattest part of the tire. Again, slowly rotate the tire and insure that you don't note a significant in and out movement of the tire.

4. Now, do the same thing for the diameter of the tire. i.e. position the indicator, so that you can position the indicator in the center of the tire tread - close but not quite touching the tire. Again, slowly rotate the tire, checking to see if you are getting the effect of a wheel hop - or a wheel that is actually getting taller and shorte r- or not round as the tire rotates.
Once you have measured and recorded all of the date for one wheel and tire, let the trailer down, jack up the other side and get the same measurements for the other tire.

5. While doing these measurements check the wheels to see if they have any balancing weight on the wheels. If they don't, absolutely go to a good tire balancing shop and get all of the tires on the trailer balanced.

6. If, when doing the side to side measurements of the wheel and tire, as well as the wheel hop test of the tire - you find one wheel with a large problem - take the wheel off of the trailer, and install the spare. Then, repeat the measurements. You may have a bad wheel on the trailer, but find that the spare wheel is good.
You may also find that you have a bad tire on the trailer, but that the spare tire is good.

If you do find that your main wheel is bad, or your main tire is bad - and can't be solved by balancing, throw away the wheel or tire - which ever is bad and replace with a new one, that has been checked to be all right.

REW

In addition, for a visual indication of a problem, take the trailer to a shop that uses, on wheel balancing.

Many of the big semi trucks use these balancers to balance the tires on the big semi trailers.

Essentially, the wheel is jacked up slightly off of the floor. Then, a wheel spinner is brought up to bring pressure on the tire, and the spinner is turned on. The wheel be brought up to a speed of about 80 mph.

If there is any sort of out of round, balance or other issue - the spinning tire will quickly show it. Then, by using their balancing device that is mounted to the tire, can balance the entire tire, wheel, hub assembly.

If you really do have a tire, wheel - balance issue, you will see the trailer shaking as the wheel is brought up to speed. You will then see the trailer run smooth, when the wheel assembly is brought to a balanced condition.

Good luck
RE W

p.s.
If you happen to have a bench top grinder, you can essentially use this grinding motor and wheel to act as a wheel spinner.

Take the guards off of the grinder.

Have an extension cord that will allow the grinder to be turned on, when the grinder is next to the wheel.

Jack a wheel slightly off of the floor, with the trailer securely hitched to the tow vehicle.

First bring the spinner tight to the wheel and turn the grinder on. If you have a large enough grinder with enough power, you will be able to use the starting power of the grinder to get the wheel moving. If your grinder is too small, you may have to bring the grinder away from the wheel - start up the grinder, and then slowly bring the spinning grinding wheel in contact with the wheel. If you still can't get the wheel spinning, you may have to give it a manual start in the correct direction and then keep it spinning with the grinding wheel.

Although you won't be able to balance the assembly, without the proper equipment, you will get a visual indication, of any issues with the spinning wheel tire assembly.

A u-tube video of wheel spinners and balancing:
http://www.youtube.com/watch?v=_tOX3eaUsTw

Checking tire run out VIDEO:
http://www.youtube.com/watch?v=QNBzPrHO4QQ&feature=related

Check the video for checking wheel run out:

http://www.youtube.com/watch?v=B6Phsoag_zk&feature=related

I am glad to see someone else is having the same vibration issue as me. I build trailer and have never seen this problem before. I can actually watch my front axle start bouncing. This can sometime get reall vilent. I replaced my tires thinking that was the problem but it turned out to be a result of something unknown. I have shifted my boat back about 3 inches and still have about 150 pounds of toung weight. The boat pulls much better. I to am looking for answers to this problem.

I just replaced my single axle trailer tires with Goodride Tires, Chinese made just like Good Years are. I noticed a vibration above 60 MPH and could see the left side start to vibrate and the tire basically start to bounce. ST205/R15

I had moved the axle back last fall on my shorelander that has a rear bank of rollers and a keel roller in the front it also has two pads in the front one on each side near the bow but had not really towed far since this spring. I had adjusted the pads just so they contacted the hull but the vibration was there with the new tires.

The tires were balanced when I had them mounted. I returned the the tires with rims to them and they both were setup on their dynamic tire balancer that checks run out of the tire. The right tire did not pass and they rotated the tire on the rim 180 degress and then it did pass the criteria of 16u (sometype of units on their equipment). The left tire which I estimated had a run out on the OD of approx 1/8" by jacking it up and spinning prior to bringing the tire in had failed their test it was approx. 5X higher than what the spec. is for tires. The tire was replaced and retested within the spec.

Just a note this was a reputable tire dealer they claimed to have only about 4 issues in one years time with these tires. Note they normally DO NOT check for out of roundness even though the equipment is available they simply balance the tires on the rims. If you get new tires I recommend asking them to check the run out of the tires as well as balance them. If they don't have the equipment to do this find someone that does. Most tires are now made in China the quality is not always there. As long as knowone complains there isn't a problem.

I also will be moving my pads on the bow tighter to the hull as that seemed to stiffen the trailer up along with the tires not being out of round I should be set. I'll try to post back when I return from Canada hopefully no issues.

I have the exact problem with a snowmobile trailer. I tried everthing suggested to you except squaring the axels and nothing changed. I'm convinced its out of square but I don't use it enough to care. Drives you nuts though, doesn't it.