Mechanical gauges are much cheaper than electrical but the trade off is the sensor is attached by a 6' lead that can't be taken off. You can't cut or bend the lead too sharply. The lead is a capillary tubing that contains a liquid like alcohol which expands driving the gauge. So if you bend it too far it will pinch and stop the fluid from expanding. That said, I bought the Sunpro Style Line water/oil temp gauge at Autozone for around $17. Sunpro® An electric full sweep gauge like this will cost around $100+ Also since the lead is only 6' and can't be adjusted, placement of the gauge is limited.

These are the parts I used for the installation.

Here's the gauge. It comes with a few brass adapters pictured.



I got a variety of grommets but ended up only using the 13/16OD X 1/2ID grommet. A tube of silicone to seal the hole I made.



I bought a brass 1/2" T. Even though the trans lines are 3/8ths I wanted more room for the sensor and for fluid flow. Also bought two 1/2" to 3/8ths push on barb adapters.



As you can see the sensor has plenty of room for flow through the T.





Also got some Harbor Freight special protective wire wrap.



I chose my spot for a hole. On the tranny hump, in front of the shifter. I step drilled starting small and worked up to a 1/2" drill. Then used a dremel and grinding wheel to make the hole a little bigger so the sensor nut could go through. The material is not very thick there. It's just a bad angle. The drill just wants to slide up on the hump. If you have a 90 deg adapter it would be easier. I put some primer on the bare metal.





Here's a shot from underneath looking up at the hole. Lots of room up there.



part 2 to follow, too many pics I guess...

So then the fun began. The sensor has to go through everything first. The faceplate that the gauge bolts to. Then I put the grommet on (I could have cut it but wanted it to be completed circle) then I routed everything through the hole. Went along the original trans cooler lines to my new cooler lines and put in the T. Covered the caillary tube with the split sleeve protective wire wrap (which was a pain to do by myself, in the truck to push some, under the truck to pull some, over and over). Then I put a zip tie on the wire wrap to hold it up so it wouldn't fall through the grommet and silicone sealed the hole as best I could. Here's a pic or two...









I placed my gauge here. I cut a little notch out for the line to go through. It's a little hard to read but it works and like I said before, with just a 6' lead, placement is limited. I could probably remount it and make it face the driver a little better but I'll just wait and see how it goes.





As you can tell I did not hook up the light. At this point I don't think I will. I don't tow and I have no plans for night time wheeling.

There is just enough capillary tube slack left to be able to lift the console cover off if needed. So like I was saying, not a lot of line to work with so the gauge goes where it fits I guess.

Seems like it would've been fairly simple to notch the plastic where the cubby is, and put the gauge in there to look a little cleaner. That way you would be close to the astray light to tap that for powering the lightbulb. Just my 2 cents.

Yeah that would have worked also. You'd need to drill the two holes to mount the gauge and then drill a 3/4" hole towards the back for the sender to go through.

Ooo, nice. Good write-up btw

I like the idea of not spending $100 on a gauge. This is gonna be something great to build on. Nice write up.

Awesome write-up! I've been wanting to install a trans temp gauge for a while and have only found write-ups that show how to install the gauge itself and not the sender. Thanks for showing the fittings you used! Like someone said above, this is a great starting point and will let me build off of this!

Why not just use the factory live data from the ecm to read trans temp? I just have the tranny temp on my phone.

one reason:
96 and 97 don't have that option.

second reason even if you have 98+:
validate/cross-check the ECU temp w/ analog measurement