Bolts Provided with Hitch Will Not Fit in Nuts Welded Into Vehicle Frame

Updated 09/03/2020 | Published 09/01/2020

Products Featured in This Question

Curt Trailer Hitch Receiver - Custom Fit - Class III - 2"

(29)

$343.40

Battery Post and Terminal Cleaner - Wire Brush

(15)

$4.56

Question:

Bolts seem to not fit.. Seems to be too big for the holes in my vehicle. Dont know if wrong size bolts were sent or what bt my question is what size bolts are required for a 2005 Mitsubishi Endeavor trailer hitch?

asked by: Renard H

Expert Reply:

Your Curt # 13569 Class III hitch uses M10 x 1.25 x 35 hex bolts.

Typically what happens on older vehicles or vehicles that have spent time somewhere that uses chemical de-icing agents on the pavement in cold weather is that road crud and corrosion get built up on the threads of the nuts welded up into the vehicle's frame. Once this buildup gets severe enough, it makes it difficult to get the bolts threaded in, and it seems as if the bolts are the wrong size. 99.9% of the time it's a matter of road grime and corrosion, in almost 15 years working here I can only recall a handful of incidents where a hitch got sent out with the wrong hardware.

So, how to fix the problem? Start by spraying a bunch of spray lubricant up in the nut, then give a good scrub with the wire brush on a battery terminal cleaner like # DW00254. You might need to do this a few times. If that fails to clean the threads well enough, you'll need to use a thread tap to clean the threads out.

expert reply by: Mike L