Will TracRac SR Sliding Ladder Rack Fit 2018 GMC Sierra 1500 with Ultra Flex Tonneau Cover

Updated 07/21/2020 | Published 01/21/2019

Question:

I have a 2018 GMC sierra with standard bed. I have a bed cover Ultra Flex by undercover. Will this work with the ladder rack?

asked by: Ronnie B

Expert Reply:

Based on my research it looks like the UnderCover Ultra Flex Tonneau Cover installs completely inside the bed rails of your 2018 GMC Sierra 1500. Since the Thule TracRac SR Sliding Truck Bed Ladder Rack # TH43002XT-781 mounts on top of the bed rails the two systems should work well together. The only potential issue with this ladder rack and hard folding covers like these is that the panels on the cover, specifically the outer seals, might rub up against the rails for the TracRac when folding the tonneau up. This won't prevent it from operating but may over time cause wear on those seals.

This ladder rack is one of the few options available that mount on top of the bed rails so it will still be your best option. I also really like the T-track base that allows you to slide the crossbars along the bed rails to adjust for different sized loads. It has a weight capacity of 1,250 pounds.

I have attached a short video demonstration on this rack along with the written installation instructions that you can check out as well.

expert reply by: Chris R

Ivan

6/13/2020

Will this fit on a 2016 Chevy 1500 6 1/2 ft bed.i have a ultra flex by under cover

Chris R.

6/17/2020

Yes, the Thule TracRac SR # TH43002XT-781 is a confirmed fit for your 2016 Silverado 1500. It will work great with your existing Ultra Flex cover assuming it does install completely inside the bed rails.

Ivan

6/18/2020

@ChrisR it does mount on the inside of truck but was concerned about the rubber lining that stops the water from getting in bed.manufacturer says you need 4 inch clearance on bed rails

Chris R.

6/22/2020

@Ivan That rubber lining will likely rub up against the ladder rack rails a bit when folding it up. It's not enough to prevent normal operation but may wear down the seal more over time.

Kristin M.

7/17/2020

Will it fit on a 2018 Ford F-150 short box with the Undercover Ultra Flex cover?

Chris R.

7/21/2020

As long as your Undercover Ultra Flex Cover does in fact install completely inside the bed rails, the TracRac SR Sliding Ladder Rack is a perfect option and will be compatible. For your F-150 you'll use part # TH43002XT-508 for the 5-1/2 foot bed or part # TH43002XT-501 for the 6-1/2 foot bed.