Torque Specs for Attaching Leaf Springs

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Question:

What’s the torque spec on the bolts attaching these leafs to the trailer and shackle?

asked by: Darrin

0

Expert Reply:

You will need the U-Bolt Kit item # APUBR-1 to use the 4-Leaf Double-Eye Spring for 3,500-lb Trailer Axles - 27" Long item # SP-210275. The kit uses 1/2 inch diameter nuts that you will want to torque them down to about 70 foot pounds.

expert reply by: Jerred H

0

Jsmie

9/13/2025

What about 4000lb axle with double eye 26" long leaf springs with 1/2 inch bolt. Whats all those torque along with the shackle

Jerred H.

9/14/2025

@Jsmie 50 ft- lbs for both the MORryde Suspension Upgrade Kit for Tandem Axle Trailers item # MR46ZR with 2-1/4" shackles or item # MR98ZR with 3-1/8" shackles. These kits come with the bronze bushings, wet bolts and shackle straps. You'll want to go with the kit closest to the size of your current shackle straps.

Answer 1

The torque requirements for leaf spring u-bolts depend on the diameter of the u-bolts that are being used. If the gross weight of your tandem axle trailer is 7,000 lbs, then you likely have two 3,500 lb axles. Typically 1/2 inch diameter u-bolts are…

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Answer 2

There is no specific torque rating for shackle bolts. You'll want to ensure that the bolts you use are long enough so that when installed you will have at least 2 threads protruding from the nut. Make sure that the bolt you're using has a…

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Answer 3

The LED Identification Light Bar for Trailers over 80" Wide - Submersible - 9 Diodes - Red Lens #MCL93RB has the wiring and housing for the individual sealed lights #AL91RB to fit. The only way to help them stay in place a little better is to…

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Answer 4

Hello Ryan, thanks for reaching out. Yes axle U-bolts are not meant to be re used so you will definitely want to replace them. For a 3,500 lb 2-3/8" diameter axle, the longest we carry are the 5-1/2" U-bolts like what come with the #APUBR-1…

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Answer 5

Hey Brent, thanks for reaching out! Your 2021 Jay Feather 24BH will have 3,500 lb axles so you'll likely need one of the following: - 27" Long Leaf Spring #e97SR - 25-1/4" Long Leaf Spring #e54SR I don't have a way to look up the…

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Answer 6

Since your 3,500 lb trailer axle leaf springs are flat and measure 26-1/8 inches the correct replacement would be the #e54SR which measures 25-1/8 inches.

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Answer 7

Hello Mark, thanks for reaching out. When replacing leaf springs, it is important the new springs are identical in length to the old ones. There is a small amount of tolerance, like 1/2" or less, but any more than this can throw the suspension…

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Answer 8

Hey Mark! Assuming they are 25-1/4" leaf springs I recommend the 3-Leaf Double-Eye Spring for 4,000-lb Trailer Axles #e57SR. These are our in house brand and will save you some money. If you would prefer to stick with Dexter we also have the…

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Answer 9

Assuming you are using 1/2" diameter U-bolts like #APUBR-1 for your 4-Leaf Double-Eye Spring #e54SR, you will want to torque the nuts down somewhere between 45 and 70 foot pounds. The shackle bolts at the end of the springs don't require a…

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Answer 10

In order to determine if a breakaway system is required on your trailer you will need to contact your local DMV. This will vary from state to state. However, it is a good ideal to add a breakaway system regardless of your state's regulations as…

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Answer 11

Many states in the U.S. and provinces in Canada require break away kit. In order to determine the specifics for where you live and where you plan to travel, you can check with the state and federal departments of transportation for the area. Specific…

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Answer 12

Hey Mark, the camber that the Dexter 3,500 lb axles like the part #7359765 have will be right at zero when the trailer is on the ground with the weight of it on the axle. If on the lighter end you might see -1.

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Torque Specs for Attaching Leaf Springs

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