Transmission pan adapter for temp gage?

4Runner4Leon

4Runner4Leon

Senior Member
Looking for ideas on the best way to tap into the pan to install a sending unit for my Autometer trans temp gauge.

I don't want to braze, so I was thinking of getting a bulkhead fitting with a crush washer, and drilling a hole in the pan. Maybe something like this (which would still require me to find a matching nut for the back side):

https://smile.amazon.com/gp/product/B00062YVNE/ref=ox_sc_act_title_2?smid=ATVPDKIKX0DER&psc=1

Or this?

https://smile.amazon.com/gp/product/B000CJ0626/ref=ox_sc_act_title_1?smid=ATVPDKIKX0DER&psc=1

Has anyone used something along these lines that they would recommend?
 
Register to hide this ad
56ad5a158a3cca78608d190bfad9581b.jpg


Not my picture but this location works. I saved this picture to do myself. Good luck on using a bulkhead fitting. It drive me nuts thinking there is always a potential leak chance not welding it.


Sent from my iPhone using Tapatalk
 
19963.4lsr5 said:
Not my picture but this location works. I saved this picture to do myself. Good luck on using a bulkhead fitting. It drive me nuts thinking there is always a potential leak chance not welding it.
Click to expand...

Thanks, I saw that too. But I'm not sure why the risk of the bulkhead fitting leaking is any higher than a drain plug leaking??

I should add, I do plan to tack the retaining nut of the bulkhead fitting to the pan, in case I want to either tighten it a bit more, or replace the gasket in the future, without having to drop the pan again.

BTW, I couldn't see the pic in my browser, but was able to find it on the phone app. Here it is for others, just in case:

 
Last edited:
Have you considered using a T fitting on the transmission fluid sending line (the one that goes to the radiator)? That is what I did and it was super easy to install.

I just bought a brass T fitting and installed male barbed ends on either ends of the T. I screwed the sensor on the bottom part (had the leg of the T facing down) and used hose clamps on the male ends. I zip tied it securely underneath in a safe spot and hasn't leaked a drop in over a year.

Just a thought
 
Most transmission vendors want to know pan temps as this is the "ambient" temp of the fluid as it goes back into the trans, so the pan is the preferred location for a probe.

Cooling solutions, like a thermostatic relay to control a trans cooling fan, are usually installed after exit on the way to cooling - fluid will be much hotter there than in the pan.

You want to know the post-cooled fluid temp in the pan. Aside from aesthetics, I see no reason not to braze a nut into the pan for a temp probe.
 
thegipper said:
Have you considered using a T fitting on the transmission fluid sending line (the one that goes to the radiator)? That is what I did and it was super easy to install.

I just bought a brass T fitting and installed male barbed ends on either ends of the T. I screwed the sensor on the bottom part (had the leg of the T facing down) and used hose clamps on the male ends. I zip tied it securely underneath in a safe spot and hasn't leaked a drop in over a year.

Just a thought
Click to expand...

I have, and in fact I just finished reading your thread on the subject :). Lots of good ideas there.

Maybe I'm just being stubborn, but I think the pan is a better place for the sending unit - but I do see that it's a subject of much debate on this forum.
 
Adding it to the pan really isn't that big of a deal either, especially if you can weld.

I've removed the tranny on my rig (the old tranny that shit the bed) so many times, I swear I can do it blind folded.

I highly suggest using a rubber or cork gasket on the pan instead of FIPG/RTV. Removing that crap from the pan the 1st time is such a PITA. I installed a reusable rubber one (think it was fel pro?) and it has never leaked a drop even after reusing it like a dozen times. You never know when you may need to drop the pan again and cleaning that crap off is for the birds....
 
Last edited:
thegipper said:
Adding it to the pan really isn't that big of a deal either, especially if you can weld.

I've removed the tranny on my rig (the old tranny that shit the bed) so many times, I swear I can do it blind folded.

I highly suggest using a rubber or cork gasket on the pan instead of FIPG/RTV. Removing that crap from the pan the 1st time is such a PITA. I installed a reusable rubber one (think it was fel pro?) and it has never leaked a drop even after reusing it like a dozen times. You never know when you may need to drop the pan again and cleaning that crap off is for the birds....
Click to expand...

In fact I am planning on using a rubber gasket (it came with the filter, so it's a freebie at this point). If it doesn't seal for some reason, I can always drop the pan again and use FIPG, without having to do any scraping!
 
thegipper said:
Have you considered using a T fitting on the transmission fluid sending line (the one that goes to the radiator)? That is what I did and it was super easy to install.

I just bought a brass T fitting and installed male barbed ends on either ends of the T. I screwed the sensor on the bottom part (had the leg of the T facing down) and used hose clamps on the male ends. I zip tied it securely underneath in a safe spot and hasn't leaked a drop in over a year.

Just a thought
Click to expand...

Hey Mike, I'd like to see more info on how you did it. Could you provide a link?
I want to add an aftermarket gauge so I can read trans temps on the 98 3rd Gen I just purchased. If any write-up you've done doesn't show it, I'd like to know what gauge you bought, where you mounted it in the cabin and how you ran the wire. Thanks!
 
octanejunkie said:
Considering it's just a screen to keep flies out you should be fine :D

You gonna use some sealer on that rubber just to be sure no leaks or nah?
Click to expand...
Phew :).

Yeah, I plan to hit the rubber gasket with a super thin layer of fipg. On both sides.

Sent from my SM-G900P using Tapatalk
 
You must be carefull using RTV on a gasket. It becomes a lubricant and causes the gasket to push and pucker while tightening. When I do something like that I'll put RTV on one side and then put a weight on the pan or valve over until the RTV hardens. And leave the other side bare.


Sent from my iPhone using Tapatalk
 
You must log in or register to reply here.

Members online

Total: 519 (members: 3, guests: 516)

Forum statistics

Threads
278,312
Messages
3,554,085
Members
248,016
Latest member
Advally Service

Share this page

Trending content

Back
Top