Free Tool

Tandem Slide Calculator

Overweight on your axles? Calculate exactly how many holes to slide your trailer tandems to get legal.

Updated for 2026 FMCSA regulations • Mobile-friendly • No signup required

Watch Video Guide

How to Slide Tandem Axles

Learn the proper technique for sliding your tandem axles to redistribute weight and get legal at the scales.

Weight distribution
Pass weigh stations
Proper technique

Axle Weight Calculator

Enter your scale ticket weights

LBS
LBS

How Tandem Sliding Works

The tandem slider on your trailer allows you to redistribute weight between your drive axles and trailer axles. By moving the trailer wheels forward or backward, you change where the cargo weight sits relative to the axles.

Slide FORWARD

When: Your DRIVES are overweight

Moving the slider toward the cab shifts weight from the drives to the trailer axles. The trailer wheels move closer to the load's center of gravity.

Slide BACK

When: Your TRAILER is overweight

Moving the slider toward the rear doors shifts weight from the trailer to the drive axles. The trailer wheels move away from the load's center of gravity.

The Math Behind It

Each hole on the slider rail represents approximately 250-500 lbs of weight transfer, depending on your trailer's hole spacing and total load. The formula is:

Holes Needed = (Overweight Amount) ÷ (Weight Per Hole)

For example, if your drives are 1,500 lbs overweight and each hole transfers 250 lbs:
1,500 ÷ 250 = 6 holes forward

Federal Weight Limits (FMCSA)

Axle ConfigurationMaximum WeightNotes
Steer Axle12,000 - 14,000 lbsVaries by tire rating
Drive Axles (Tandem)34,000 lbsMost common limit
Trailer Axles (Tandem)34,000 lbsMost common limit
Gross Vehicle Weight80,000 lbsInterstate highway max

* Some states have lower limits on certain roads. Always check state-specific regulations.

Frequently Asked Questions

2026 Master Guide to Tandem Weight & Bridge Law

FREE

📘 The 2026 Master Guide to Tandem Weight & Bridge Law Compliance

The complete guide to understanding axle weight limits, tandem adjustments, and bridge law calculations. Stay legal on every scale!

  • Federal Bridge Formula explained simply
  • State-by-state weight limit variations
  • Tandem slider positioning strategies
  • Scale house survival tips
  • Overweight ticket prevention checklist
Download Free PDF Guide

No email required • Instant download • 100% Free