Determining The Correct Capacity Gen-Y 5th Wheel Pin Box For A Grand Design Momentum 397TH

Published 10/17/2023

Question:

I have A Momentum 397TH. GVRW of 21K. Gen-Ys table says I need the 6.5K model. Any experience with this? In you video Jake has a momentum toy hauler and is using the 5.5K Gen-Y. What is the GVRW of his Tailer? Thank You,

asked by: John S

Helpful Expert Reply:

Gen-Y's calculation for pin weight is a safe guess, but isn't the most accurate so the only way you'll get the correct capacity Gen-Y 5th Wheel Pin Box is to fully load the trailer and go to a commercial scale to measure the pin weight. With the 5th wheel trailer attached to your truck you'll drive on the scale so that only the 4 wheels of the truck are position on the scale. Write down this weight and then detach the trailer and weigh the truck again. The difference between these two weights will be the loaded pin weight of your trailer. Once you have that number you can look at the Gen-Y chart again and choose the correct capacity.

You'll also need to verify that the bolt pattern is an appropriate fit. The # GY46FR you were looking at is designed to fit a 1621 bolt pattern. If you have a sticker on your current pin box that says the LCI #, Serial #, and RPO # then I can use this information to determine the correct fit. If not you can use the attached help article below to measure for the bolt pattern.

The trailer Jake installed the Gen-Y Hitch Shock Absorbing 5th Wheel Pin Box # GY46FR is already gone so I'm not able to check what the GVWR is.

expert reply by: Kevin C