Can Longer Shackle Straps be Added to Tandem Axle Trailer

Question

Question:

Hi I have a 2 axle trailer and I put 3 inch shackles on the front and back will it still work or is it not safe

asked by: Scott

0

Expert Reply:

When replacing shackle straps they should be the same length as the ones that were previously on your tandem axle trailer (if possible); replacing them with longer straps will result in additional play in your trailer suspension which could lead to additional wear or other issues and longer ones are not going to provide you with added benefit.

For a tandem axle trailer it is common to have 2-5/8" shackle straps such as part # 115052. I recommend using these if they were the same length as your previous shackle straps.

I added a link to our selection of shackle straps for you in case you had a different length, as well as a link to a help article on trailer suspension which I recommend checking out.

expert reply by: Kyle S

0

click to enlarge

Dean

3/10/2020

What if I have 3 shackle straps, can I go back to the 2.625 without any issues??

Reply

Chris R.

3/11/2020

Most likely this would be fine, but if the trailer currently uses 3" shackle straps it would be best just to stick with those to maintain current suspension performance. Is there a reason you want to move to shorter straps other than availability?

Reply

Dean S.

3/11/2020

I needed to replace all the bolts, bushings and straps because im rebuilding and saw on the website that most tandem axles are 2.625. so I just switched..

Reply

Chris R.

3/12/2020

I see - that makes sense. I don't think the shorter units will cause any issues. Just be sure they're still long enough to have a nice upward angle when unloaded.

Reply

Philip F.

3/10/2024

I have a question regarding spring position. I have an old Magic Trail boat trailer (twin axle) which I intend to renovate this year. It has 2x2 square axles and 20'' DE 3 leaf springs. The axles (with no load) appear are both slightly rotated and tip in toward the equalizer so the springs do not sit level. Is this normal / acceptable? The outermost hangers are about 2-1/4'' and the center hanger is 6" I was considering longer shackles but having read your earlier advice to Scott i'm not now sure.

Reply

Kyle S.

3/11/2024

@PhilipF Yep, this is normal. I would go ahead and keep the same length shackles as you have now.

Reply

Justin

9/9/2024

@KyleS what does it mean when the axels have no load and springs should sit level? I’m trying to figure out the correct shackles as I had one side with small and one side with big. Do I jack the whole trailer off ground then look at the springs and detrimen the correct side ?

Reply

Kyle S.

9/10/2024

@Justin Yes, that would be the correct move to determine right ones. You definitely want them all to be the same size.

Reply

See All (5) Replies to Philip F. ∨

Andy

12/22/2025

I have a 3500lb Tandem axle cargo trailer. There have been 2 times the shackles on one of the axles have flipped, (over extended). The most recent time when it flipped it broke the U bolts on the one side. Is there a way to correct this from happening, is this a common issue

Reply

Jesse M.

12/22/2025

@Andy Not exactly a common issue but it is typical for this to happen on tandem axle trailer when longer-than-stock shackles are used. What’s happening is the longer shackles are allowing too much suspension travel, which lets the equalizer and shackle rotate past their intended range. Once they flip or over-extend, the suspension can bind, and that shock load is often what leads to broken U-bolts or bent components, just like you experienced. Reducing the shackle length should fix this.

Reply

Answer 1

To slightly lower your trailer that has had an "axle flip" kit installed you would want to use slightly shorter shackle straps, not longer ones. Shorter shackles will let the axle rest closer to the trailer frame, which lowers the trailer…

view full answer...

Answer 2

Well shackle length is mainly based on the height difference between the front and rear hangers. The rear hanger normally doesn't hang as low as the front so that the shackle can offset the difference and add the ability to move. What is the…

view full answer...

Answer 3

The shackle straps included in the Lippert Tandem Axle Equa-Flex AP Kit - Wet Bolts - 3-1/8" Long Shackles #LC64FR you mentioned are 3-1/8" center to center and 4-3/8" overall length as shown in included diagram. Using the longer…

view full answer...

Answer 4

Hi Mark; I recommend upgrading your shackles as well while you're at it using the Dexter Heavy Duty Suspension Upgrade Kit for Single Axle Trailers #K71-358-00. This includes wet bolts, bronze bushings, and 1/2" thick shackle straps so you…

view full answer...

Answer 5

Trailer manufacturers don't usually keep a record of parts like these that they install at the factory, so I cannot be sure as to the exact length of the shackle strap that would have come originally on your trailer. With this in mind, a 3-1/8…

view full answer...

Answer 6

If the shackle straps are within a 1/2" of what you normally had, say the 2-5/8" #115052 to 3-1/8" #TRSL313, you should be okay to install them. Just make sure that all of your shackle straps match though. If you are using the longer…

view full answer...

Answer 7

The first thing I would check on your trailer is the capacity of the springs. You need to be sure the spring capacity is rated at 1/2 the axle capacity. That way 2 springs equal the capacity of the trailer axle for proper fit. Check the arch of the…

view full answer...

Answer 8

We have replacement shackles that are 2-5/8 inches bolt hole center to bolt hole center with the part #115052 but we do not sell these in a kit like you asked about. Then for wet bolts that will work with these that come with matching nuts you'd…

view full answer...

Answer 9

There should be enough free play in the shackles to allow them to move. There is no specific torque rating for shackle bolts. The first thing you should make sure of is that the bolts you use are long enough so that when installed you will have at…

view full answer...

Answer 10

Before you consider re-tapping the threads, re-check to make sure you have the right sized Anode Rod. I reached out to my contact at Suburban and they advised me that your water heater has a 3/4" NPT (National Pipe Threading) and it has 12…

view full answer...

Answer 11

The Road Armor Shock Absorbing Equalizer Kit part #LC696740 are taller than most other standard equalizers so you'll likely need the longer 3-1/8" shackle straps when using them, the Lippert AP Kit part #LC52SV is a go-to for this as it has…

view full answer...

Answer 12

Hi Brian, To ensure you're getting the correct fit you'll want to measure the spacing horizontally from eyelet to eyelet and vertically from the hanger bolt eyelet down to the center of the shackle strap eyelets on your current equalizer. The…

view full answer...

Can Longer Shackle Straps be Added to Tandem Axle Trailer

Product Page this Question was Asked From

Featured Help Information

Miscellaneous Media

Continue Researching