How Tight Should Leaf Spring Shackles Be?

How do I calculate my U bolt length?

The U-bolt size is given as Diameter(A) x Distance(B) x Leg Length(C).

Additionally the bend type must also be given to avoid problems in specifications of semi-round bend shapes..

Which end is the front of a leaf spring?

A leaf spring can either be attached directly to the frame at both ends or attached directly at one end, usually the front, with the other end attached through a shackle, a short swinging arm. The shackle takes up the tendency of the leaf spring to elongate when compressed and thus makes for softer springiness.

Do leaf spring shackles move?

Because the mounted main eye cannot move, the shackle eye allows the springs’ length to change. The other purpose of leaf spring shackles is to keep your vehicle balanced.

Is it OK to reuse leaf spring U bolts?

I would like to ask some questions and start a discussion related to U-bolts used to clamp leaf spring stacks on the suspensions of vehicles such as small to full size pickups, jeeps, and larger work trucks. Generally, most after-market U-bolt manufacturers recommend to never reuse U-bolts.

How do I know if my leaf springs are worn out?

Look out for these tell tale signs that you need to replace your leaf springs:Squeaky sounds while your truck is in motion.Slouching on one side.Sagging in the back.Diminished handling.Trouble hauling and towing loads.Suspension bottoming out.Cracks on leaves.

How much do I torque leaf springs?

A 1/2 inch diameter bolts should be torqued between 45 ft/lbs and 70 ft/lbs. A 9/16 inch diameter bolt should be torqued between 65 ft/lbs and 95 ft/lbs and a 5/8 inch diameter bolt should be torqued between 100 ft/lbs and 120 ft/lbs.

How tight should spring shackle bolts be?

Tightening the shackle bolts too much will squeeze the shackle straps against the leaf springs and the whole suspension system will bind and cause problems. The best thing to do when tightening down shackle bolts is to use lock nuts and tighten them until they are snug and then backed off 1/4 turn.

Can you over tighten U bolts?

There’s a good reason not to over-torque ANY bolt! Because it actually makes the connection weaker and MORE likely to come apart! Torque specs are set where they are for a reason. Bolts stretch as they are tightened.

Which direction do leaf springs go?

Normally the band is placed forward of the axle on the trailer but it really does not matter which way the band is oriented. Measure the distance from the center of the spring eye on one end of the spring to the center of the spring and then to the center of the back spring eye. The on center distance should be equal.

When should you change leaf springs?

In any case, leaf springs should be checked at regular durations, which would be every 12,000 miles for most trucks. With certain trucks, there might be a shorter recommended interval, so it’s always best to check with your auto manufacturer.

Do lowering shackles affect ride?

Changing the shackles won’t affect ride at all. Since its not stiffening or softening the spring.

Should leaf springs be lubricated?

Modern leaf springs do not need lubricating with oil — which may damage any anti-friction material between leaves. Spray them instead with a silicone-based lubricant. With most modern cars, leaf springs are found mainly in the rear suspension. Raise the end of the car to clean them.

How long should leaf springs last?

about 200,000 milesOn average a set of leaf springs for a standard pickup truck or van will have a lifespan of about 200,000 miles. This number is not written in stone, and some vehicles will break their springs with far less than 200,000 miles on them while others will go well beyond the 200,000 mile mark before they break.

Is there a front and back to leaf springs?

Double eye leaf springs like the part # SP-169275 do not have a front or back designation. Slipper springs like the part # SP-038275 do have a front and back.

Why would u bolts have to be tightened correctly?

centre bolts hold the spring together for assembly and help locate the spring onto the axle in the correct position. Correctly tightened ubolts are what holds the springs firmly in place on the vehicle when driving. … Most times just supplying the vehicle make, model and year will be enough.

What to torque U bolts to on leaf springs?

If the U-bolts are 9/16 inch diameter, the torque specs should be between 65 to 95 foot lbs. If the U-bolts are 3/8 inch diameter, the torque should be between 30 and 50 foot lbs. view full answer…

When should the U bolts on a spring suspension be re torqued after installation?

Also, TMC recommends running the truck on a course where maximum articulation of the suspension occurs after installation, then loading the suspension before retorqueing the U-bolts. They should be retorqued again between 3,000 and 5,000 miles after replacement.

Should you replace U bolts on leaf springs?

U-bolts are a vital part of your suspension system and should never be reused. Failure to replace or properly fit your U-bolts when maintaining or servicing your suspension could cause premature failure of your leaf springs or other components with catastrophic results.

Can I replace just one leaf spring?

A used leaf spring is generally interchangeable with a new one as long as both are the exact same size. Therefore, when you replace an old leaf spring with a duplicate, it will restore the performance of the truck to its earlier driving condition.

How tight should bolts be?

Tighten all U-Bolts until they are snug only. Tighten in the sequence shown to approximately 1/3 of recommended torque.

Can you put leaf springs in backwards?

The spring eyes dont allow the spring itself to be installed backwards (dimentionally different diameters for front and rear bushings). The fact that you have a height problem is actually, and unfortunately, almost normal.