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Transmission Bottom Center Bolt

2066 Views 6 Replies 4 Participants Last post by  denissca
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I have 2016 Canyon SLT Diesel 4x4 with about 7k miles (owned since new). Today looked underneath and saw a 18mm bolt loose (under tightened) by about 1/8 inch. Have not caused any issues/leaks yet. I gave it few turns and stopped wondering if this was done on purpose. So, is this is a factory assembly mistake or not? Anyone had this bolt loose?
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I haven't crawled under my truck yet because I haven't changed the oil yet (about to change within a month or two) so I don't know what's under there yet. Rockcrawler could probably give you a good answer on this though.

My guess, based on the look of it, and where it's placed and what you said...probably the drain bolt for the transmission? I would think that if it is that, it should not be loose....
You do not have to crawl to see it as it is located in the visible area. In fact i noticed it accidentally when i dropped something next to the truck, when i picked up the object i looked under truck and saw a loose bolt. Thank you!
not sure what it is, but I'll look when I get back to my truck. Its definitely not supposed to be loose. Go ahead and snug it with a ratchet. When I see what it is I can give you more idea of how tight it should be. I just made an oil change vid last night and put it on YouTube. I rewatched it and I can tell it's not the trans pan or the oil pan. Looks more like a diff or t-case with the way it clamshells together there
Transfer case. That shouldn't be lose. I would check the oil in it.
Good catch. Haven't gotten back home but based on the pic I agree with him.

To check the level of the fluid in the t case you need to pull the fill bolt (looks like the drain bolt but higher up) out of the back of it. Fluid should dribble out. If not, stick your pinky in to see if it's full up to the bolt hole. If not, and it wasn't leaking then it could already be empty.

It probably takes the blue t case fluid that GM likes to use. Can't remember the name (auto trak II maybe) but it's like $12/qt. Check your owners manual to be sure on the correct fluid.
Thank you for replies! Yes, that looks like a transfer case drain bolt. I had Free GM Dealer first Service about a thousand miles ago. I know they put the truck on the lift and done the inspection (seen them doing it). They should have noticed it back then even if technician was not the one who got it lose. Looks like i need to schedule a service with the dealer and have them correct it since it is under warranty. Thanks again!
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