A Sprinter with factory longitudinal roof rails is already one step ahead: the van has a movable mounting channel running front to rear. The remaining question is not whether a crossbar can be attached. It is whether the attachment hardware actually matches that channel and whether the crossbar kit matches the roof.
The quick answer
For a Mercedes-Benz Sprinter equipped with OEM longitudinal roof rails, DVA's DualTrack-T crossbar kit mounts through the separate OEM T-bolt mounting kit. The live kit includes eight 25 mm × 25 mm T-slot bolts, eight washers, and eight nuts—the hardware needed to attach two transverse DualTrack-T rails to the factory channels. Choose the High Roof or Low Roof crossbar variant to match the van.
Why the T-bolt question keeps coming up
The channel looks simple until an owner tries to source hardware by shape alone. In the Sprinter-Source thread “T-Bolts for OEM Roof Track”, DAWg134 described the practical annoyance: “I'd prefer a T-bolt so that I'm not chasing a nut up and down the channel trying to install a bolt through the plate.” The thread then branches into modified elevator bolts, drop-in nuts, ground hardware, and questions about whether a fastener must enter from the end.
A second thread, “T bolts for VS30 roof rails”, starts with Happy29 trying to add a solar panel between existing awning mounts. That is the real constraint: installed equipment can block end access, so hardware selection and insertion order matter before the roof becomes crowded.
“I've got to mount a solar panel in between the mounts for my [awning]. (So I cant just slide some t nuts in from the open end)”
Happy29, Sprinter-Source, August 2022
Identify the roof you have before ordering
“OEM rails” means the longitudinal channels already installed on the roof, not the factory roof attachment locations hidden under plugs on a rail-less van. Those are different starting points. DVA's OEM T-bolt kit is explicitly for vans with factory longitudinal rails. It is not required for the standard DualTrack-T installation that uses the normal mounting hardware supplied with the crossbar kit. The High Roof and Low Roof labels identify crossbar fitment geometry; they are not different hardware-capacity claims.
If the roof is bare, start with a longitudinal rail system rather than trying to substitute the OEM-channel kit. The LoadSpan-T roof rail system is the DVA route for 2019-present 144, 170, and 170 Extended Sprinters using the factory roof mounting locations. It provides continuous L-Track and 25 mm T-slot channels for later accessories.
