Th400 Dipstick Length

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Pierre

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Recently I had my TH400 dipstick break. Current dipstick length is from end to end 35 inches, and I cannot seem to find this exact same size online.

With that being said from everything I read the th400 dipstick should be 25 inches long not 35 inches.

Has anyone ever seen this longer dipstick in a th400? Or is it possible someone before me used a th350 dipstick tube and stick? Is it possible to use a th350 tube/stick in a th400?
 

Vbb199

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I bought a stock 6 lug converter th400 from a camper that had a super long dipstick in it.
 

Pierre

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I bought a stock 6 lug converter th400 from a camper that had a super long dipstick in it.

Not sure what my th400 came out of but it does have a very long dipstick which I cant seem to find anywhere else. Currently its in a 1985 K20. I am worried about getting the stock th400 length tube because then it will be almost 10 inches lower and un-reachable.
 

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I'm gonna measure my own th400 dipstick and tube right quick out of curiosity

Edit: the one in my c10 is 27"
 

Vbb199

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Alright, I looked at results for like a 1978 p30 with a 454 , and it uses a much longer dipstick apparently, like a little over 40" lol
 

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The full mark should be at the same level as were the pan/case parting line. If your dipstick is too short (HA!) use a tubing cutter to trim just a little off the dipstick tube.
 

VMF531

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GMC 1991 Suburban 3/4T, 4wd, 6.2L diesel.

Last year I had a problem in that the dip stick tube broke at the mounting.

I found the tube by doing a search using the part number on the dipstick 15659781. My dip stick length measures 34 1/4” with the handle folded.

Do a search for your dip stick part number.

I found this web site with drawings. Hope this helps.

 

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@Matt69olds Would a 34 inch TH350 dipstick and tube fit a TH400 case? Basically the one that @Cdncarnut posted a link to. I ordered the only one listed on Summit Racing for my truck, a Pioneer 768023 which measures 29 inches, and is the same one listed for every single TH400 vehicle across the board on Rock Auto as well. Even "P" vehicles list that dipstick, I'd hate have one that short in a van or stepvan. My broken dipstick measures 31 inches from the hood at the handle to the break. I don't want one that sits lower down, I like the OEM that is easier to get to.
 

nvrenuf

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I checked a th400 I’ve got and the actual stick length is 33-7/8”, it would be slightly longer if you included the handle but you want the length of the stick itself. Older sticks have a pull loop and later model sticks have a locking flip over pull handle, because of the different pull gadget designs the total length can vary between the 2 (as well as applications, vans can be longer etc).

Here are my pics, you can see the part number on the stick.
 

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DoubleDingo

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I checked a th400 I’ve got and the actual stick length is 33-7/8”, it would be slightly longer if you included the handle but you want the length of the stick itself. Older sticks have a pull loop and later model sticks have a locking flip over pull handle, because of the different pull gadget designs the total length can vary between the 2 (as well as applications, vans can be longer etc).

Here are my pics, you can see the part number on the stick.
Thank you for that information. That coincides with the length I thought mine was. My question, though, is will a TH350 dipstick and tube, mainly the tube, will it fit the TH400 case? If so, the one linked by @Cdncarnut would work for my TH400. I would prefer a 34" versus a 29". The 29 will put it about at the top of the valve cover height, whereas the 34" would keep it where it is at about mid-air cleaner height, and much easier to check the fluid levels.
 

nvrenuf

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I gotcha, I didn't realize the OP was from '22. I can't answer the th350 question, I've never owned one.
 

DoubleDingo

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Yeah, I was creating a new thread when some hits popped up, so I clicked on this thread and saw what may work for my truck since the one I got last night, while it will work, it's a tad short for the truck. I too, have never owned a th350. I think the tube diameter is the same, but I need a transmission guru to tell me for sure. I know @Matt69olds is one of them. @HotRodPC is another. @bucket may know. There probably a ton of members that know, but I don't know that they know.
 
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