Axle Placement When Building A Three Axle Trailer

Question

Question:

when I build this trailer where do I place the axles on a three axle trailer.

asked by: Daryl

1

Helpful Expert Reply:

In order to calculate where the axles would go on your trailer, there are several things that need to be taken into consideration. You will have to mock up the trailer with the suspension and axles to get the weights needed to determine where the axles need to be positioned. I have attached a photo that shows you the formulas needed to determine the correct position of the axles.

To help you determine what components you will need, I have linked you to a help article for trailer suspension, and the parts needed. I have also attached a photo that has a diagram of spring hanger dimensions. It lists the hanger kits based on the springs you choose to use.

I would recommend slipper springs because they can handle heavier weight than double eye springs, and also have fewer moving parts.

expert reply by: Jeffrey L

1

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Eddie B.

2/18/2026

I am building a 28' flat bed trailer with 3 axles. I have the placement based on your picture. My question is will 16" rims and tires have enough room when driving on uneven terrain

Kate F.

2/18/2026

@EddieB I wish I could give you a direct yes or no answer, but whether 16" wheels and tires will have enough clearance depends on more than just wheel size. Overall tire diameter, axle center to center spacing, and suspension travel all play a role, especially on a triple axle trailer that will see uneven terrain. Tire to tire clearance between axles and vertical clearance to the frame or deck at full suspension compression are the main things to verify. What axle spacing measurements are you planning to go with, center of axle to center of axle?

Edward

2/18/2026

@KateF. 34" center to center of the 3 axle. 29.5 - 34- 29.5 on spring hanger centers then it would be 34" center to center of axles

Kate F.

2/19/2026

@Edward You will be safe going with a 16" wheel. What you really need to look out for is the tire size and brand you choose. If you are going to be on really uneven terrain, a 3" gap between tires would be ideal, but you will want at least a 2" gap. Overall tire diameter can vary not only by tire size, but by brand as well. For a 3" gap with 34" axle spacing, you will want a tire diameter no larger than about 31". For example, if you went with the Strider ST235/80R16 Radial Trailer Tire with 16" Revolver Black Mod Wheel, 8 on 6-1/2, LR E # TA27AR, the overall diameter is 30.8". The weight capacity is 3,520 lbs at 80 psi. These also have a pretty sweet speed rating, although I do not recommend towing your triple axle trailer at 87 MPH, especially on rough terrain. So yes, you are safe going with 16" wheels, just look out for that overall diameter. If you have a specific wheel you like, let me know what it is so I can find the right wheel tire combo for you.

Helpful Links

tv-demo-taskmaster-trailer-tires-and-wheels-tire-with-wheel-ta27ar.aspx

See All (9) Replies to Eddie B. ∨

Answer 1

I wouldn't get caught up in how the shackles are positioned while installing the Dexter E-Z Flex #K71-652-00. The shackles won't be hanging down like that when you put weight back on the axles and leaf springs. The fact that the angle was…

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Answer 2

The Dexter E-Z Flex Suspension Kit #K71-653-00 is the correct kit you will want for your tandem axle trailer Jerry. The 8,000lb rating is for up to the capacity for each axle.

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Answer 3

Hey Caleb, so generally what you see is that on lower capacity trailers the wheelbase between the axles is 33 inches and above like 6k or so the wheelbase most commonly seen is 35 inches. This just works out the easiest and corresponds with how most…

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Answer 4

I spoke with the engineers over at Timbren. The reason that they do not recommend the axle-less suspension systems, such as #ASR5200S01, for triple axle applications is because there is no equalization between what would be the axles of the trailer.…

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Answer 5

It is always good practice to have at least 2 inches of space between your tires whether it is a tandem or triple axle trailer. The 2-1/2 inches that you have between your tires should be enough for you to travel safely. There isn't really a hard…

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Answer 6

Hi David; I honestly wouldn't choose steel brake lines for a salt water application, even if they were stainless. A better option would be the Hydrastar Hydraulic Brake Line Kit #HS496-152 or #HS496-252 with copper-nickel alloy. This has proven…

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Answer 7

Hey Mike, yes the hanger kit part #APTT5 that you referenced is compatible with the leaf springs you also mentioned #E64SR. What kind of trailer do you have?

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Answer 8

I saw you were looking at double eye leaf springs so we will assume that is what you have. In regards to leaf spring hanger spacing, the most common for a triple axle trailer is 29-1/2" first to second (center to center), 34" second to…

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Answer 9

Hey Michael, the leaf spring part #e66SR that you referenced would not work for you as it was designed for a much lighter 2,500 lb axle. So instead you'd want a leaf spring that was designed for 7k axles like the part #TRU52FR which is similar in…

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Answer 10

In the image with the suspension setup the equalizer #TREQ105 is placed between the front and second axles. Just like you have on your trailer. The front of the equalizer connects to the spring using a shackle strap and the rear is connected directly…

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Answer 11

In order for your trailer suspension to function properly you will want the angle of the shackle strap to be towards the axle so that as the leaf spring compresses and expands it will have somewhere it can go. Otherwise, you will not get the optimum…

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Answer 12

Yes we do have a chart that shows how to space the axles of a triple axle trailer with a hanger kit like the #APTT5 that you referenced. I attached this chart for you to check out as well. The bottom section of the chart is for use with springs that…

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