The Mysterious Axle Wrap Problem - Pt 1

Solving A Wide Range of Issues

Because the Road\Active Suspension is more than just a helper spring (which also does the job of a sway bar and traction bar) we are constantly receiving inquiries from truck owners regarding a wide range of issues.

Earlier this year, I had several people contact me with an issue they hoped we could help solve. This issue seemed to be more unique to one particular make and model truck. The problem was a rear end “shudder” when accelerating at a low speed and became worse when the vehicle was carrying a load. Before getting into the fine details of what causes this issue, we suspected this was a case of axle wrap!

Here Is What Was So Odd

Every person that contacted us had a 2011 Ford F150 Ecoboost Supercrew. Ford introduced the Ecoboost engine in 2011  and in the same year this vehicle was named the Motor Trend Truck of the Year. To complicate matters, we discovered there is a slight difference in the rear leaf springs of the standard 2011 F150 and the 2011 Ford Supercrew Ecoboost F150.  When looking to find the cause of an axle wrap issue, one should first have to look under the hood, to see what engine the vehicle has. Diesel engines are notorious for causing an axle wrap/wheel hop issue due to the high amount of low end torque that is produced.  This causes down force on the rear, when the axle twists and causes the rear of the leaf springs to de-arch and then rebound.

Let's Learn More About This Truck

The standard 2011 F150 5.0 V8 pushes out 360 horsepower with 380 foot lb of torque, compare that to the Ecoboosts’ 3.5 V6 that pushes 365 horsepower with 420 foot lb of torque. The torque curve on this is similar to a diesel truck and according to Ford spokesman Michael Lord, the truck generates 90% of it’s torque at just 1700 RPM. Now that’s some engine!

The Ecoboost max tow is rated at 11,300lbs, 1,300lbs more than the standard 5.0 V8. While Ford obviously designed these trucks to be able to handle this sort of weight, there is bound to be the odd problem when introducing a substantial upgrade such as this to market. Being in a niche automotive market, we seem to have found the problem that has plagued a some owners of this model Ecoboost pickup.

So What Can We Do?

Several of the people that had contacted us looking for a solution, explained that they already had their truck in the Dealer shop several times to no avail. One  truck owner explained how his truck had spent nearly a month repeatedly in the shop, eventually having the leaf springs replaced, but even this did not solve the problem.  Eventually a Ford engineer flew in to try to identify and solve the issue. He was shocked when the engineer after driving the truck, told him it was axle wrap, and this was to be expected and there was nothing he could do about it!

What happened next? Tune in next week for the rest of the story!