A truck with a wallowy ride and squeaking leaf springs
The complaint was simple. The truck was uncomfortable to drive. The leaf springs were squeaking. The whole rear end felt heavy and wallowy — like the truck wasn’t holding itself up properly.
The owner had been wearing it for a while. He figured it’d settle down. It didn’t.
Why this matters
A wallowy truck has lost its load capacity. The rear end bounces over every bump, the driver fights the wheel, and the ride is rough on the body and the load. Push it far enough and the leaf springs crack — and a service job turns into a recovery job by the side of the road.
The diagnosis — leaf springs bent the wrong way
Most leaf springs sit in a U-shape — curved upward in the middle, holding the chassis up off the axle. If you park a new spring next to a worn one, the difference is obvious.
The set on this truck were doing the opposite. They were curving downward, the inverse of where they should be. That’s a spring that’s been pushed past its working range for too long, or had a rough run with a heavy load over rough roads — usually both.
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What that means in the cab
Once springs invert like that, they can’t carry rated load anymore. Put weight on the back and the truck drops too far. The rear bounces over everything because the spring has no working travel left. The squeak is the leaves rubbing where they shouldn’t be.
We pulled the worn set and put new springs on. Fresh U-shape, working travel back, ride sitting flat.
Takeaway
If your truck feels heavy and bouncy in the back, or you’re hearing a squeak that wasn’t there last month, that’s the leaf springs talking. Catch them early — they’re a service job. Catch them late and they crack. Book it in and we’ll have a look.
