Can You Use 8,000 Lb Wheel Bearings on a 7,000 Lb Trailer Axle

Updated 07/21/2025 | Published 04/28/2023

Products Featured in This Question

Bearing Kit, 14125A/25580 Bearings, GS-2125DL Seal

(3519)

$39.94

Bearing Kit, 14125A/ 25580 Bearings, 10-36 Seal

(3519)

$43.50

Question:

Hello, I have a 2017 Grand Design Momentum 350m with the dual lippert 7K axles. Im in the process of bullet proofing the camper to give peace of mind for the years to come. I already upgraded from E to G rates tires, put all new drum brakes and pads, in the process of replacing leaf springs and adding sumo spring. My question, the axle bearings that came with the drum kit are the Dexter 7k. Are there a set of bearings that I could get that are rated for 8k that would fit existing 7k axle? I am just looking to gain some additional safety factor for the peace of mind. Thanks in advance

asked by: Justin H

Expert Reply:

The wheel bearings for a 7,000 lb axle are not exactly the same as the wheel bearings for a 8,000 lb axle, the inner bearings are the same but the outer bearings are not, they have different outside diameters. Therefore, the two are not interchangeable. That said, even if you could upgrade this would not increase capacity nor should it really give you any more peace of mind. The weight capacity comes mainly from the axle beam and spindles. If you need replacements for your wheel bearings, the Bearing Kit part # BK3-210 (2.125" seal) or part # BK3-200 (2.250") are a great option.

expert reply by: Conner L

Pete

7/21/2025

That’s not entirely true Connor. The 8k hybrid axles still use a #42 spindle with a 5 (3/8unf) bolt flange. You could put 8 lug 8k hybrid drums onto 7k axles and have the benefit of a heavier duty outer bearing. Possible you’d run into stud size issues as most 8k are 5/8 studs while 7k are 1/2” or 9/16” generally. The failure point of a 7k axle many times is the outer bearing in real world scenarios so it’s not a terrible idea, though you’re not technically gaining any axle capacity because of the tube dimension. One could argue however something like a bent tube or spindle usually won’t leave you stranded on the side of the road, whereas a bearing will. It’s also arguable that a bearing failure generally can be more dangerous because it usually happens at speed and there’s potential for the wheel to come off etc. If you’re hauling near max gvw all the time it’s definitely not a terrible idea to splurge on 8k hybrid hubs during a drum replacement. I can’t say it would be money well spent to upgrade unless you’re replacing your drums anyways. I’m sure Connor can help you with some part numbers. Feel free to correct me if I’m wrong on anything , but I think it’s quite accurate.

Jameson C.

7/21/2025

@Pete Excellent insight Pete. I would agree with everything you said and if Conner still worked here I am sure he would too. Or if he didn't we would all tell him he's wrong.