Aftermarket dipstick tube leaks

[RustyRatRod]

Been in mine for 10 years. Never leaked a drop. Good price too.($17)
Chrysler SB Compatible Dipstick - Car Sump
View attachment 1716413891

Yeah, I've brazed a bracket onto stock tubes a lot. That looks nice. Yall got one for a slant 6? lol

 

[Swinger 340]

Yeah, I've brazed a bracket onto stock tubes a lot. That looks nice. Yall got one for a slant 6? lol

Remember, you need the stick along with the tube. Maybe, not on a car but a van dipstick works great on a truck. It brings the stick up to the front of the radiator and easy to get to. No need to climb into the engine bay. As I think you were saying RustyRatRod, you can cut down a tube from any Mopar motor, as long as you have the stick to fit. All the tubes fit the motors the same, just the outer tubes may be different.

 

[Woody500]

I've used those chrome dipstick tubes.
They can work okay, BUT- the chrome plating makes the bottom of the tube too big for the hole in the block. SOP is to grind off the plating, being careful not to get into the base metal; then driving it in. If someone got a little carried away and ground off too much it'll be a sloppy fit and as you found out, RTV (of whatever color) will only stop the leaking for a given amount of time.
I really like Inertia's idea of tinning the end and reinstalling to stop the leak on an existing tube.
I also like that Summit (Edit- Oops, I meant Mancini!) has a raw steel tube now- if it's a quality piece that's sized correctly, then that eliminates all the hackery. Plus you can then paint them block color the way Ma Mopar intended.

Factory uses Compression brass fitting, like that, on the Marine dip tube, which is mounted in the cast aluminum oil pan on LM 318s. Not sure about 340s.
Surprised it's not leaking, at that angle it might not be filly seated, either.