I cannot find the right U bolts (1/2 x 4 x 3.5) anywhere

[acarleson]

Hi everyone,

I absolutely CANNOT find U bolts for a 4x3 (4" tall, 3" wide) trailer frame. Looking for 1/2" hot dipped galvanized bolts. After some digging, I found u bolts that go vertically (that is, they are 3" wide and 4+ inches long) but I can't find any that let me bolt things on to the side (that is, U bolts that are 4" wide between the legs and at least 3.5" long or so in the leg).

Looking for 1/2" hot dipped galvanized U bolts.

I just can't believe that in all the trailer parts websites, west marine, home depot/lowes, even amazon, nobody sells this U bolt. Am I just looking in the wrong places? I've tried hardware sites, everywhere.

Anyone know of any trailer parts dealers who just have EVERYTHING? I see a lot of 4x3 trailers in my boat yard and a lot of them have sideways U bolts, so they are definitely made, I just can't figure out where to get them!

Thank you in advance

 

[roscoe]

What is a sideways u bolt ?

"CANNOT find U bolts for a 4x3 (4" tall, 3" wide)"

"I can't find ... U bolts that are 4" wide between the legs and at least 3.5" long "

huh?

Probably have to go a little larger.
3060T245

 

[briangcc]

Got a heavy truck repair shop in your area? Or custom spring shop? Cause they can make them for you.

My Dad had some made years ago for our trailer at a custom spring shop.

 

[Scott Danforth]

my local trailer shop has a few hundred different styles of U-bolts in-stock. have you checked your local trailer shop?

 

[acarleson]

Thanks, all. Just to clarify @roscoe I just mean that on a trailer that is 4" tall and 3" wide, I can find plenty of bolts that fit vertically on the frame (so they are 3" between the legs and at least 4" long) but I'm looking for bolts that fit horizontally on the frame (so they're 4" between the legs and at least 3" long).

I have checked my local trailer ship (and even called a few in larger cities around me) and this size doesn't seem to be easy to find. May have to look into custom, which seems SO odd for something as common as a 4x3 trailer frame. Appreciate the responses

 

[robert graham]

Maybe open up your search to include stainless steel bolts, nuts, washers…

 

[acarleson]

yeah good point, thanks, stainless will work too. Appreciate it

 

[dingbat]

What your going to find is that a number of trailer manufacturers use non-standard size hardware on their trailers.

Having said that, here are your bolts.

ROAD KING 1/2" Square Stainless Steel U-Bolt, 5" x 3" #12X35UBSS

Stock# 5430051ROAD KING Stainless Steel U-Bolt includes two stainless steel lock nuts. Leg Length (A) = 5", Leg Width (B)= 3", Thread (C)= 2"

www.easternmarine.com

This site carry most of the standard trailers sizes

U-Bolts, Zinc Plated Steel at Trailer Parts Superstore

Trailer Parts Superstore offers a wide variety of Zinc Plated U-bolts for trailer repair. Easy to use online store with secure checkout.

www.easternmarine.com

 

[acarleson]

@dingbat Thanks. Unfortunately these won't work—The legs need to be greater than 3 inches, as my frame is 3" wide, and the holes in my mounting hardware are 4" (actually more like 4 1/16"), so that's why I noted that I need bolts that are 4" between the legs and at least 3.5" long or so. I'm just shocked that these don't seem to exist! lol

 

[dingbat]

@dingbat Thanks. Unfortunately these won't work—The legs need to be greater than 3 inches, as my frame is 3" wide, and the holes in my mounting hardware are 4" (actually more like 4 1/16"), so that's why I noted that I need bolts that are 4" between the legs and at least 3.5" long or so. I'm just shocked that these don't seem to exist!

Call them.
The 3” is tube size not the actual inside dimension

 

[acarleson]

@dingbat thanks! When you say 3" tubing size is not the actual dimension, do you mean that a 3" tubing size U-bolt is not actually 3", or that my trailer is not actually 3"? I have no idea what my trailer "tubing size" actually is, but it definitely measures almost exactly 3" across, so I would need U bolts that are about 3.5" (at least) to accommodate the nut

 

[Scott Danforth]

call these guys. https://www.sturdybuiltonline.com/

 

[dingbat]

@dingbat thanks! When you say 3" tubing size is not the actual dimension, do you mean that a 3" tubing size U-bolt is not actually 3", or that my trailer is not actually 3"? I have no idea what my trailer "tubing size" actually is, but it definitely measures almost exactly 3" across, so I would need U bolts that are about 3.5" (at least) to accommodate the nut

What exactly are you doing?
I too have 3x4 tubing. Replaced every nut and bolt on the trailer 4 years ago. Had no problem finding hardware.

These are 3x5 unbolts in the picture

 

[acarleson]

@dingbat that photo is helpful! Yours are going up and down, so they're really useful for bolting things that go on the top or bottom of the frame. I have these weird side bunks that get bolted to the SIDE of the frame, so I need bolts that go sideways on the frame. I can't find the exact mounts I'm talking about but it would be something similar to this, where the bolts need to go sideways:



And my holes are about 4-1/16 apart, so I can't use a U bolt that is 5" between the legs, and it has to be at least 3" long to go all the way across the width of the frame, if that makes sense? It basically has to be a U bolt that is 4 or 4 1/16" wide (the distance between the legs) so the whole height of my frame can fit (and the U bolt ends can go into the holes), and long enough that it can cover the whole width of my frame plus the width of the bracket and still have room to put a nut on, so about 3.5" long in each leg.

Happy to clarify more if that doesn't make any sense! It's hard to describe

 

[roscoe]

Would this work?

Mount Type	Threaded
Thread Size	1/2"-13
Inside Width	4"
Height	4 5/8"
Thread Length	3"
Capacity	2,000 lbs.
Material	Galvanized Steel
Center -to-Center	4 1/2"
Leg Diameter	1/2"

 

[acarleson]

@roscoe that looks like it will work! I have no idea how you found that, I thought I scoured mcmaster-carr and did not see anything. Did you find it on their site or somewhere else?
Thank you!!!

 

[roscoe]

Just went to their site.
Its the one I posted a link to in my first response.
Here are all their square u-bolts.

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

Anyway, get to work on that trailer, its time to go boating.

 

[acarleson]

Will do! Thanks!!

 

[jworks]

Hi everyone,

I absolutely CANNOT find U bolts for a 4x3 (4" tall, 3" wide) trailer frame. Looking for 1/2" hot dipped galvanized bolts. After some digging, I found u bolts that go vertically (that is, they are 3" wide and 4+ inches long) but I can't find any that let me bolt things on to the side (that is, U bolts that are 4" wide between the legs and at least 3.5" long or so in the leg).

Looking for 1/2" hot dipped galvanized U bolts.

I just can't believe that in all the trailer parts websites, west marine, home depot/lowes, even amazon, nobody sells this U bolt. Am I just looking in the wrong places? I've tried hardware sites, everywhere.

Anyone know of any trailer parts dealers who just have EVERYTHING? I see a lot of 4x3 trailers in my boat yard and a lot of them have sideways U bolts, so they are definitely made, I just can't figure out where to get them!

Thank you in advance

I had that issue with a Venture boat trailer. I went to the Venture website. Bingo, they were there. So if you are still looking go to the trailer mfg website.

 

[JimS123]

If Fastenall doesn't have it, they are not made. If you don't have a local store, go online. I have done some custom projects and NEVER failed to find it there.