U-bolt on leaf springs

[Likes to tow]

I cannot over emphasize the importance of continuous monitoring the tightness or torque on the U-bolts of your axle!!! This is one maintenance item I have never checked. If the U-bolts become loose the spring center bolt can shear and the axle can move backwards on the springs. This tilts the tire out and your trailer will move rather sideways down the road eventually destroying the tire!! The leaf spring centering bolt is held in place by the u-bolts clamping the axle and springs together. It can shear easily if there is movement. Very dangerous condition but it is preventable......keep the u-bolts tight. Don't overtighten however because this can cause them to fail. Use a torque wrench and tighten to specs......about 70 lbs on most trailers Leaf spring centering bolts are replaceable and can be purchased at most auto parts stores like NAPA.

 

[txloser]

That’s a good heads up. I’ve never bothered with this on any trailer I’ve owned. On the Solitudes they had that recall a while back for overtightened u-bolts, so 70 lbs seems reasonable as a general number.

 

[Wileykid]

I know it is controversial, but you should also replace the u-bolts with new ones when you take them off. The place I used to put on my Roadmaster system re-used the original u-bolts, after the first trip, I found two that were very loose. I replaced all u-bolts with new ones, and torque striped them with a paint pen, that way it is a quick look to make sure they are good.

Here is the recommended torque on the bolts that were printed on the Roadmaster instructions, and were obtained from the manufacturers:

Dexter Axles
Item Torque Range (ft-lb)
3/8" U-bolt .........................................................30-50
7/16" U-bolt ........................................................45-70
½" U-bolt with hex nut .......................................45-70
½" U-bolt with flange nut ...................................70-80
9/16" U-bolt .......................................................65-95

Lippert Axles
2,000- to 8,000-pound capacity axles
Bolt Type
Torque Specification (ft-lb)
U-bolts (2,000 lb axle) .........................................35
U-bolts (3,500 lb axle with ½" U-bolts) ................50
U-bolts (5,000 lb axle) .........................................65
U-bolts (6,000-8,000 lb axles) .............................90

 

[Likes to tow]

Good info........Thanks! Hope everyone is outside today checking their U Bolts!!! Pulled boat trailers all my life, had 3 fifth wheels and did not know U bolts was a maintenance item. First time I have ever spent 3 hours on the side of the road too!

 

[Wileykid]

Good info........Thanks! Hope everyone is outside today checking their U Bolts!!! Pulled boat trailers all my life, had 3 fifth wheels and did not know U bolts was a maintenance item. First time I have ever spent 3 hours on the side of the road too!

One should also check the bolts on anything they can find under the trailer, brake parts, shackle bolts, etc. I have had a brake caliper come off its mount due to improper torque from the factory. It really isn't enjoyable being on the side of a freeway.

 

[JKJavelin]

Like the poster above, last year I had 2 brake calipers fall off, because the shop I had replace the pads the previous year did not use blue Locktite on the caliper bolts. I had heard that they could come loose, so I would check them occasionally, but my timing was off. Then I discovered that there was no sign of Locktite.
JK

 

[jjbbrewer]

Good discussion. Based on recent experience, this is the suspension spares kit I carry. What's not shown is I also carry a spare leaf spring and CRE3000 equalizer.

As for the leaf spring center bolts, here's what I ordered that seem to work on my Alcan springs. I think they're suitable for OEM springs as well.

 

[BrokeDown]

When I was on my way to MORryde to get IS, I heard a clunk coming from the trailer. I asked them to look into it. When I returned to pick up the RV, they showed me a loose U bolt on one of the axles. I reported it to GDRV and shortly after, they sent out a notice to owners.

B

 

[Steven@147]

Been there, done that, had the same problem !