I have one of those Diversi-Tech receivers with the integrated lock in my current Dak. I had a rough time getting it out last year due to rust (I was taking it out to put in a bike rack - told my son I was removing the stinger and putting in fangs :P ), but thought I had resolved the issue by giving it a thorough dose of graphite. No such luck: I went to remove it yesterday and it would not budge! I tried REALLY hard to twist it and only ended-up breaking one of the 2 keys.
So..I bought some dedicated rust penetrator spray and squirted it all over, waited a few minutes and still no go. Waited a few hours and still no go. I am beginning to suspect I will need to cut the darn thing off (it's aluminium, so I am guessing it won't be TOO bad to cut.) From the DT Web site, it looks like there is a round steel tube that engages the cams that lock it in place, so I think if I try to cut it off and leave that in place, I should be able to twist the tube and unlock the cams, then remove it.
Before I go to that extreme, any other ideas on how to get it out?

Thanks,
John

 

Kroil is what I would try. Or find a way to get some ATF(automatic trans fluid) in there. Soak time of a few hours may be required. Although Im not familiar with that particular brand, you should be able to spray kroil into the mechanism, let it soak for a while, then insert your key and gently tap lock with a hammer while trying to unlock it. If that doesnt work, there is the infamous "Vicktor Wrench" thats guaranteed to get it off.

 

Torch the truck side to get it to expand and loosen up.. combine that with your penetrating oils and you might get somewhere. Then use gobs of anti-seize next time. Aluminum and steel really don't like being together, they can practically weld themselves together..

 

I tried heating, more oil, etc and no luck. So I got myself one of the Diablo "Steel Demon" blades for my reciprocating saw and some thread cutting oil and had to make some slices. I first tried just lopping the end off, but had to do some more cuts to get the rod that actuates the cams exposed enough to get a set of pliers on it (in retrospect I probably could have just cut a notch for a straight-slot screwdriver!)
Hated to do that as I REALLY love the DT hitch receiver. I plan on buying another one soon, but will make sure it is one of the gen 2 models (they are supposed to be better sealed and had some lube in them to help prevent this.)
Here is an excerpt from an email they sent me about their second gen models "SECOND GENERATION air & water tight designed parts that help keep water, penetrating oil, and road chemicals out of the ball mount even if the rubber covers are unintentionally left open."
They also mentioned a way to identify the second gen models "our 2nd Generation design change in April 2009 (This is ball mounts stamped before 0409 and ball mounts that do not have a DCT serial number stamp)", so I need to find a way to check this on one I buy in the future. I will also NOT leave it in all winter (I had left it in pretty much since I bought this Dak in mid/late 2010 and had had it for at least a year before that on my 2007 Dak.)
Here are some pics of the carnage after I finally got it off.

John

http://i1208.photobucket.com/albums/...r/IMAG0034.jpg

http://i1208.photobucket.com/albums/...r/IMAG0035.jpg