Thanks! I guess you’re in the same boat I am: the cover interferes with the measurement. The main thing I’m looking for is to see if there’s a difference between the bulkhead and tailgate measurement; the difference is what matters more than the precision of the measurement.
The reason I want to know is when I ordered my bedrack from Xtrusion Overland, they asked if my bed is straight (bed width same at bulkhead and tailgate) or tapered (bed narrower at tailgate). The bars are custom cut to fit a particular truck model, year, and bed size, rather than being an adjustable, one-size-fits-all design. The picture below may help picture this.
I answered straight, knowing that the 5’7” bed is straight, and that the Classic/4th Gen is tapered. I assumed, as perhaps incorrectly, that the 6’4” bed on the 5th Gen is also straight.
But a few things led me to question that assumption. First, when the rack is fully loaded with rooftop tent and other gear, the tailgate can sometimes not latch properly. This is especially true of my wife and dogs are in the tent.
Then, I removed the rack recently, and it kind of popped out of the brackets that hold it to my Retrax cover.
So I think my bed rack may be an inch or two too wide. Thus, it may have been pushing the bed sides out a bit, especially at the tailgate. Had I specified tapered bed, I would have gotten shorter crossbars that properly fit my bed.
This, aside from the cover, is why I didn’t simply take the measurement myself: my bed may have been forced wider at the tailgate that it would normally be. So my measurement would be wider than what it
should be.
No big deal; I just need to disassemble the rack, cut the aluminum crossbars (easy to do with a metal cutting blade on a miter or chip saw), retap the bolt holes, and reassemble. (And maybe, if necessary, use a ratchet strap to bring the bed back into alignment at the tailgate end; I’m probably making this sound worse than it is).
But I first want to confirm the bed is indeed tapered, and by how much. That’ll give me a guide as to how much to trim the crossbars.
I may try to find a 6’4” bed on a dealer lot nearby (probably easier to find a quad cab) and take the measurements myself.
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