TH350 dipstick tube and dipstick for a TH400???

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DoubleDingo

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I asked yesterday in an old thread, I decided to start a new one today. Will a th350 dipstick tube fit the th400 case? To me, they should be the same. But I am not that familiar with both transmissions to know for a fact.
 

Matt69olds

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I’m pretty sure the tube won’t interchange, otherwise why would they have different part numbers? The dipstick might work if it’s the correct length.

The full mark on the dipstick should be at the parting line between the case and oil pan.
 

Ricko1966

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I asked yesterday in an old thread, I decided to start a new one today. Will a th350 dipstick tube fit the th400 case? To me, they should be the same. But I am not that familiar with both transmissions to know for a fact.
Sir I have no idea if I had to bet I'd say they are not the same,dam it I hate you,just remembered I have 2, I can check visuals for you tomorrow if nobody has a definite answer. Can I ask why you are in need of one,do you have a damaged one or just don't have one? Heck I'll put this up in case it does anyone else some good, my K was someone else's project,I ended up with it. He made a remote dipstick tube. IDK why anyway it was a stock tube with a section removed sleeved on the outside with a hose,and clamped to the firewall. I'm betting he had a broken tube and was trying to get by,tell he had time,money or correct parts.
 

DoubleDingo

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@Matt69olds and @Ricko1966 I asked this question in the thread below this one in the list. Instead of retyping it all, I am going to copy and paste it here for redundancy. Give me a couple minutes to get the stuff already typed out and paste it here.

Edit 1: From other thread... @Cdncarnut posted this link for a 34 inch th350 dipstick and tube... https://www.hedman.com/product-detail/7165


Edit 2: From other thread... @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.


Edit 3: From other thread... 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.
 
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rusted nuts

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There's 2-3 driffent ones for the th 350 two have driffent o rings.
 

DoubleDingo

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It appears the th350 and th400 have the same tube diameter. The same 768023 on rockauto and summit appears for both. I have the 768023, it's shorter than stock. So. That, to me, means the 34" th350 dipstick and tube that @Cdncarnut posted should work with a th400. Maybe? No? I really don't know. I just have it in my brain that GM being bean counters and having huge amount of parts that interchange, that a dipstick and tube for a th350 should also work for a th400. Especially when Pioneer has the same part for both.
 

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Since I am trying to find a replacement for my broken trans dipstick, I bought this one from rockauto.

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It seems to be the same length as my broken one, fits the tube, and has the locking feature. I think I will rock this one for the time being and order the 34 inch th350 one I mentioned as a backup, since the th400 and th350 aftermarket dipstick and tube part numbers are identical.
 

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Since I am choosing to be a guinea pig on this, I will post up what I find out when I finally get the 34 inch one. Just ordered it at 09:09, hopefully will get it by this weekend
 
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Had to check the thread heading^^^^^^^^.......34 inch WHAT???...........got it now!!!!
 

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Had to check the thread heading^^^^^^^^.......34 inch WHAT???...........got it now!!!!
I figured some of the members on here that have done way more tinkering through the years than I have would have had a definitive answer. Since they didn't, and I am an out of the box type of thinker, I am taking the plunge to compare the two. I plan to return the Pioneer 768023 that I bought from Summit because 29 inches is too short for squarebody truck. If it was a car or even Crusty Biscuit or some other style truck the 768023 would probably work just fine being 29 inches. But our trucks came with 34 inch dipsticks from what I've seen, making them easier to grab and check the tranny fluid level. If the 34 inch doesn't work or fit the th400 I'll offer it up on here for someone with a th350. As it sits the locking dipstick for an 82 c20 seems to fit my truck just fine. I haven't had a chance to drop the pan to see where the marks are in relation to the case. The filters I ordered have to be returned. The photo showed the non-dacron filter type, but I got the dacron-filter type filters. Looks like a trip to the local transmission shop where I got the last one, granted they are still in business after the dempanic, I mean plandemic, I mean .....
 
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DoubleDingo

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I like it when stuff ships quickly. I should get the 34 inch today. If I do I can compare the 34 and 29 tube diameters and report what I find after work.
 

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I just went with the Lokar one, while the convenience of it not being rigid formed is nice. Has a couple draw backs, you need to use their full tube adapter (which is small and can get lost) and it can also get hot when pulling dipstick checking fluid levels after driving.

But it seals nice and looks great, comes in two lengths I believe and you can mount it where it works best .
 

DoubleDingo

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I just went with the Lokar one, while the convenience of it not being rigid formed is nice. Has a couple draw backs, you need to use their full tube adapter (which is small and can get lost) and it can also get hot when pulling dipstick checking fluid levels after driving.

But it seals nice and looks great, comes in two lengths I believe and you can mount it where it works best .
If I can't find an OEM option or an aftermarket option that is close to OEM, I may have to go the lokar route.
 

TJ1978

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If I can't find an OEM option or an aftermarket option that is close to OEM, I may have to go the lokar route.
It's nice but I will say another slight downside to Lokar is, it is tad overpriced and or expensive. But it looks nice and it works, especially in situations you are finding yourself and I found myself in. Lokar was the answer for me. For my blazer and '69 c10.
 

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I got a "Lokar" look alike for a TON cheaper off the interwebs for my Chevy II. Works well. Same one on Kooper's S10 with the 700R4
 

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