350 dipstick tube

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midwest

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I've owned my truck for around 20 years and the dipstick tube has always been loose. Being lazy I have always jut put slight pressure on it when pulling the dipstick out so the tube doesn't come out. It's never leaked or caused an issue but after changing the oil today I asked myself why I've never secured it. Is there supposed to be something like gasket sealer that actually holds these in, or is it just friction from the factory and mine is wore out?
Curious what I should do, besides waiting for it to eventually come out while I'm going down the road.
 

Buck69

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20 years is a long time to be loose. It is likely warn down enough that replacing it is the best option. If you're lucky, the block won't be the same.
I have had good success sealing and locking loose tubes (diesels) in place by adding knurling to the portion of the tube that seats in the block. It increases the diameter slightly and will center it when reinstalling. Thoroughly clean/degrease both the tube and the (block) bore. Apply a thin coat of green Loctite to the tube only and tap it into place from the lower portion of the tube.
 

midwest

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So if I replace, do the new ones just press in or seal somehow? I should have mentioned the truck probably hasn’t had 5-7,000 miles on it during that time…
 

PrairieDrifter

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Slight press fit when new, I would run a small bead and smear of good rtv around the base of the tube and stuff it in. Rather than sifting through dipsticks, hoping for the right one.
 

AuroraGirl

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this guy recommends putting the lose part in a vice and slightly making it out of round and then using a sealant on it and reinstalling. I should do this sometime(mine is loosey goosey)
 

bucket

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Sometimes the new aftermarket ones are a pain in the donkey to install because the press fit is too tight. And it sucks even more when one of those cheap chrome ones later break off in the block.
 

Big Ray

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I was on a road trip in oct. In my K5.
My dipstick broke, right where it's stamped with the slot.
Of course, I had a tranny leak. So it was at the back of my mind, "you need fluid!", over and over.
I was on a back road in nebrasks,Nebraska, saw some squares in a guys yard. Stopped got out, we shot the breeze for an hour. He pulled one out of his trucks. I gave him 20 for it. I hated to leave, I could have spent the evening talking with him.
 

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