Is There A Complete Axle Upgrade Kit For 2021 Jayco Pinnacle RV With 7K Tandem Axles?  

Question:

Expert Reply:

Scott, I’m sorry to hear that.

We do carry many of the individual parts needed for heavier axle setups, but there is not a universal bolt-on 8K axle conversion kit. To move from 7K to 8K axles, you’d need to upgrade all related axle, suspension, hub, brake, and hardware components to match the 8K rating. We’d need measurements like the hub-face-to-hub-face, spring-seat-center-to-spring-seat-center, axle tube diameter, brake size, bolt pattern, wheel/tire ratings, and ideally the axle tag info from your current Dexter axles.

One alternative worth considering, which I think would be awesome for your application, is the Timbren Axle-Less system # T84CR, since it eliminates the axle beam altogether. That could be helpful in a situation where axle tubes keep bending. It is still rated at 7,000 lbs per system, and you’d need two systems for a tandem trailer, and it would not give you the same capacity increase as switching to 8K axles. It also requires proper frame/crossmember support. But this would combine everything so you wouldn't need to worry about bending an axle, flattening your leaf springs, breaking a shackle or equalizer or anything like that.

Before ordering parts, I’d strongly recommend weighing the trailer by axle position and having the frame, hangers, alignment, and suspension inspected. Two bent axles in that few miles usually points to something that needs to be diagnosed first.

expert reply by: Andrew N

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Scott B.

6/2/2026

Hi Andrew, I appreciate your help. Yes, I do need to have it weighed and inspected. I am also looking for pricing to know about what this will cost me. Looking to upgrade: 8k Dexter axles, from hub to hub. HF: 93 Axle tube diameter 8k axles should ne 3.5", with 1/2" wall tubing unknown spring seat center Heavy duty shackle wet bolts bushings 4k axle springs.for each axle side I use Sailun ST radial tires G rated, 14 ply 91/6 studs Not looking for exact pricing, just a ball park. Thank you!

Andrew N.

6/3/2026

@ScottB Hey Scott I'm sorry to say this, but as I'm looking more into, we don't have any axles over 7,000lb capacity since that gets into some heavy duty haulers and we don't get into that market as much. Dexter does still make some 8K axles so maybe you can reach out to them or a custom axle / trailer shop in your town. I do apologize again for the inconvenience there. That said, I can help you assemble the rest of the parts if you still wish to continue down this road. First you'll want a new ubolt kit for the axle # APUBR-35. For the springs, it depends on your setup. You need to know what style (double eye or slipper), and the length from eye to eye, but I'd budget for around $100 per spring. You can look at the 7-Leaf Slipper Spring w/ Hook End for 8,000-lb Trailer Axles - 26-5/8" Long # e37SR as an example. For the brakes and hubs, you can go with something like etrailer Electric Trailer Brakes w/ Dust Shields - Self-Adjusting - 12-1/4" - Left/Right - 8K # AKEBRK-8 and Easy Grease Trailer Hub and Drum Assembly for 8K Axles - 12-1/4" Diameter - 8 on 6-1/2 # AKHD-865-8-EZ-K. You'd need to make sure the spindle on your new axle matches this since these hubs fit a #42 spindle which is common on 8k axles. It comes with the Inner bearing: 25580 (1.75" inner diameter) and Outer bearing: 02475 (1.25" inner diameter). Then all of our 8k hubs have the 8 on 6-1/2 lug pattern, so you'll need to make sure your wheels are that setup. That's common on 7k axles too so it might be fine as it is, but I'd double check. There is not really a good all-in-one upgrade kit for shackles and wet bolts, but you can likely keep your shackles then use wet bolts like # 126B2 as long as your current ones are 3" long. I think you may be better off with a complete upgrade kit like Roadmaster Comfort Ride Leaf Spring Suspension Kit w/ Shocks - Tandem 8K, 3-1/2" Axles # RM-2470-2580 which would work with a new dexter 8k axle 3-1/2" diameter. Another solution is to keep your current setup and save the trouble, then add some suspension enhancement to help support the load over the axle with underslung # SS33HR if your springs are under the axle, or overslung # SS26MV if your springs are under the axle. I know I threw a lot at you, but hopefully this points you in the right direction. It is a LOT of work to do a complete change of axle and suspension setup, but it can be done of course. You can click on any hyperlinked part to see the product page and pricing info etc. Hope this helps!

Scott

6/3/2026

@AndrewN Hi Andrew, Thank you for your research, and great advice! I appreciate your willingness to share your knowledge. Ii need to get a professional to insoect it, and see what's what. Unolts are a must with new springs. I appreciate the links and the information. This is gonna get real spendy. I like the Road.aster option, but not sure if it will wprk with my system. I will find a reputable shop with Dexter axles access, probably an actual trailer repair place, instead of an RV shop. Time will tell, I have a few months yet to save some more $. Thanks again!

Andrew N.

6/3/2026

@Scott Happy to help! And great idea, this is a lot to try and figure out without a shop seeing it. Good luck and keep me posted on which route you go!