how long should this bolt be? pic inside.. transfer case..

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Mar 5, 2008
ok.. so i i have a TC case leak. It is between the speedo gear housing, and the main body of the TC itself.

I removed two stripped bolts, and discovered that the bolt is only long enoug such that about 4 threads of each bolt would engage the TC body, holding the speedo housing in place.

this equates to about 4mm of thread length on my caliper that i measured. the entire threaded length of the bolt is 1.4cm. that seems pretty short.

before i retap this hole... do i need a longer bolt? 4 threads seems pretty minimal for engagement.
2010 pics 178.jpg
I would pull it apart and see how deep that hole is. If it has good depth to it beyond those 4mm you are getting now, clean it up with a tap and put a longer bolt of appropriate size. If that doesn't work you can move on to the next step (drill and tap, time cert etc)
well here's a couple more with the bolt in question. I do appreciate trying to slide a depth gauge in there, but there was a lot of loctice on the threads, and i wonder if the loctite would be blocking me from finding the deeper recesses of the bolt hole. i removed a 3rd (non stripped bolt... the one you can see still in place in the first pic i posted), and it was longer than the other 2. I tried to put it in the other 2 holes, but it wouldn't go any deeper than the two shorter ones i pulled out. So either they ARE the appropriate size, or the hole is filled with crap, blocking the bolt from further entrance.

the housing that accomodates the bolts seems like there should be a MUCH deeper hole than what the removed bolts suggests. look at the following pics... that bolt seems very short to me. but then, i don't know what size it should be, so maybe i'm incorrect.
2010 pics2 002.jpg
2010 pics2 001.jpg
I measured one from a spare t-case.... it's 25mm long. The one you show is definitely too short. If you get the proper length bolt, clean the t-case threads up and don't over torque it you might get lucky. Might also get a bolt longer than 25mm and grind the tip down to where there's no clearance issue and get a few extra threads.
hey i really appreciate the info. I mean, very much so. thanks.
Looks like 30mm will work and not protrude into the case at all. Assuming the hole is threaded all the way into the case, that would gain back the threads lost to stripping. Sorry I'm not an expert on these cases so be careful. The saying "if it doesn't go easy, force it" doesn't apply! ;)
Viewing per your PM.

As indicated, 4 of the five bolts should be 25mm long, the fifth even longer, so there is a fair chance you have a problem with those holes. Maybe even some broken bolts in there. Let's hope not.


Mark A.
I was able to get all the holes to accept a 25mm bolt, so luckily no broken bolts in there. the longer one, i don't recall the size i put in there... i just pulled out the long one, and checked the length vs. the apparant depth of the hole, and ended up putting a longer one in there too.

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