What are Thule T-track bolts and nuts, and what size do I need for rack accessories?

Expert Answer

Thule T-track bolts and nuts are the fasteners that slide into a roof bar’s T-slot to mount accessories like bike racks, awnings, cargo boxes, and other carriers. The right size depends on the bar’s T-track width and the accessory’s mounting hole, so there is no single universal size.

For a safe fit, check three things: the T-slot width, the bolt thread size, and the usable bolt length after washers and the accessory bracket are added. A bolt that is too short will not fully engage the nut, while one that is too long can bottom out or leave the accessory loose. If you are replacing missing hardware, compare the original bolt head shape and thread before ordering.

VANROCK does not supply Thule-branded roof rack parts, but we can help with general fastener and mounting-hardware questions for tracked machinery applications. If you are working with undercarriage parts, VANROCK supplies track bolts and nuts through its dealer network and quotes on request.

Answered by VANROCK specialists · Published 9/15/2026