U bolts
U bolts
Anyone know the size of the Ubolt that goes on a 1991 W250? Also need to know the torque spec, I was in the middle of putting a ubolt on and it snapped in half.

Good news is I have new leaf springs!! Just my luck!

Good news is I have new leaf springs!! Just my luck!
There are two different sizes. Passenger side has a larger U-bolt than the drivers twin set. The torque spec is 95 Ft lbs. wait a week or so of driving, and re-torque.
The stock ubolts are 9/16" but you can step them up to 5/8" for extra beef, but you should torque them accordingly. 5/8" ubolts require higher torque spec than stock 9/16".
You will also need to hog out the spring plates to fit the larger diameter.
I had a set of 5/8" made up at the local spring shop for cheap.
You will also need to hog out the spring plates to fit the larger diameter.
I had a set of 5/8" made up at the local spring shop for cheap.
The stock ubolts are 9/16" but you can step them up to 5/8" for extra beef, but you should torque them accordingly. 5/8" ubolts require higher torque spec than stock 9/16".
You will also need to hog out the spring plates to fit the larger diameter.
I had a set of 5/8" made up at the local spring shop for cheap.
You will also need to hog out the spring plates to fit the larger diameter.
I had a set of 5/8" made up at the local spring shop for cheap.
Oh,
I thought he wanted the spread of the u-bolt, and not the thickness of the bolt itself.
9/16" X 3 1/4" x 8 3/4" Round Bend; w/ Deep Nuts & Thick Hardened Washers; For Front Spring; Drivers Side
and
9/16" X 4 1/16" x 8 1/2" Round Bend; w/ Deep Nuts & Thick Hardened Washers; Front Spring; Passenger Side Outboard
I second the notion of having the local spring shop make them up. Cost me about $9 to have them make me a new u-bolt and it fit perfect.
Rock auto has them in stock from $6 to $9 something a piece
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according to the spring shop that did my springs, the u-bolts are a one time use product, as they're designed to stretch upon torquing. After unbolting them, they don't have the ability to re-stretch without possible failure, such as what was described in the OP, where they snap.
Registered User
Joined: Jan 2008
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From: Quinton, New Jersey (middle of nowhere)
I ordered the "9/16" X 4 1/16" x 8 1/2" Round Bend; w/ Deep Nuts & Thick Hardened Washers; Front Spring; Passenger Side Outboard" U-bot for the passenger side from rockauto and they sent me the complete wrong one, i was in a jam and googled spring shop in NJ real quick and found a spring shop 30 minutes away. He made me a U-bolt and gave me a cup of coffee for $10, Nice guy 
95 ft lbs. is what he told me to torque a 9/16 u bolt too

95 ft lbs. is what he told me to torque a 9/16 u bolt too
So I've been all over and no one has these U-bolts. Napa had one close but it wasn't long enough. Is there a place online that anyone knows I can buy these?
Willing to spend the extra money for case harden ones.

Willing to spend the extra money for case harden ones.
I ordered the "9/16" X 4 1/16" x 8 1/2" Round Bend; w/ Deep Nuts & Thick Hardened Washers; Front Spring; Passenger Side Outboard" U-bot for the passenger side from rockauto and they sent me the complete wrong one, i was in a jam and googled spring shop in NJ real quick and found a spring shop 30 minutes away. He made me a U-bolt and gave me a cup of coffee for $10, Nice guy 
95 ft lbs. is what he told me to torque a 9/16 u bolt too

95 ft lbs. is what he told me to torque a 9/16 u bolt too
Registered User
Joined: Jan 2008
Posts: 7,547
Likes: 2
From: Quinton, New Jersey (middle of nowhere)
Hahah I don't think the guy knows how to use the computer. No website.
I wish i had more than one made for this reason.
Remember the driver side u-bolts are fairly common, the passenger side one is a rare beast because its 4-1/16" wide to go around the axle housing, the driver side ones just go around the axle tube.
Rockauto HAS the special passenger side U-bolt, It's Part Number- USB042R
Hopefully they send you the correct one,
I wish i had more than one made for this reason.
Remember the driver side u-bolts are fairly common, the passenger side one is a rare beast because its 4-1/16" wide to go around the axle housing, the driver side ones just go around the axle tube.
Rockauto HAS the special passenger side U-bolt, It's Part Number- USB042R
Hopefully they send you the correct one,






