Can Heavier Leaf Springs Be Substituted to Offset Weight of Multiple 5th Wheel Slide-Outs

Question:

My 5th wheel rv was in the shop last year for unusual tire wear. Come to find out there was a broken leaf spring on the driver side rear. The mechanic said it was because we were overloaded but we had it weighed and we are actually under weight. Now, 6 months later the springs are sagging on that same side again even with the 3500lb springs on. When I look at the weighing results I see that the trailer is almost 1000 lbs heavier on that side and there is little I can do about it to distribute the weight 4 slide outs on that side including kitchen. Can I put 4500lb springs on just that side and leave the 3500lb springs on the other side?

asked by: Robert B

Helpful Expert Reply:

Your concern with uneven tire wear and suspension sag from the weight of your toy hauler's 4 slide-outs can be addressed by installing stiffer springs on that one side of the trailer. I confirmed with my technical contact at Grand Design that this is permissible and that other owners have done the same.

You will want to select springs of the appropriate eye-to-eye length to match your OEM springs and of a weight rating that is not too much higher than the OEM springs. My contact recommended 4K springs. If you happen to have 25-1/8-inch springs # e54SR you can replace these with 4000-lb spring # e57SR which is 25-1/4-inches. A 4500-lb spring like # e27SR is likely to be too stiff, according to my contact at G-D.

expert reply by: Adam R