Adapters to Use Thule Kayak Carrier on Older Style Thule Square Bars

Updated 07/27/2026 | Published 07/20/2026

Question:

I have a set of Thule 515-5031 kayak holders that work with square crossbars. I now have a car that has Thule 750X aerobar crossbars. Is there any way to retrofit my kayak holders to work on the aerobar crossbars? Thank you.

asked by: Jason H

Expert Reply:

Hey Jason,

Thanks for reaching out. Unfortunately, there isn't an adapter or retrofit kit available that will allow your older kayak carriers, which were designed for the discontinued Thule square crossbars, to be used on your newer Thule Aerobars. I wasn't able to find an exact reference for the 515-5031 part number, but everything I found indicates it was designed specifically for the older square bar system and doesn't have a compatible adapter for the current aero-style bars.

The good news is that we carry several kayak carriers that are compatible with your Thule AeroBars. If you can let me know:

How many kayaks you'd like to carry
The type of kayaks (recreational, fishing, touring, sit-on-top, etc.)
Their approximate weight and width

I'd be happy to recommend the best carrier for your setup.

What type of waterways do you typically kayak on?

expert reply by: Christopher H