5th Wheel to Gooseneck Pin Box for 2015 Keystone Avalanche

Updated 05/22/2024 | Published 05/20/2024

Question:

I need a gooseneck attachment for a fifth wheel and I was wondering if all the kingpins on the Keystone are the same?

asked by: Andrew

Expert Reply:

I believe you're referring to the pin box on your 2015 Keystone Avalanche. The pin boxes are not the same for all Keystone 5th wheels so you will need to identify what you have to find the right 5th Wheel to Gooseneck pin box.

I would start by checking for a sticker on your pin box. It may have the actual number or at least a serial number that can be used to identify it. If you can send me that serial number I would be happy to identify it for you. You could also take the VIN and ask the trailer manufacturer. If all else fails you can measure the bolt pattern which is outlined in the article below.

The # GY38FR you looked at is designed to fit a Lippert 1621 and 1621 HD. If you have one of these it will fit but you also need to calculate your tongue weight using the Gen-Y formula GVWR x 0.22 = TW. Once you have this calculation you can find the right tongue weight for the Gen-Y pin box using the chart below.

For example, if you had the 390RB with a GVWR of 15,500 lbs your TW would be 3,410 lbs. Using the chart you would need a Gen-Y with a 4,500 lb tongue weight capacity so assuming you have a Lippert 1621 the # GY38FR would be the correct replacement.

expert reply by: Robin H