[VAC] Installing a Transmission Temp Gauge

["David W. Lowrey" <dave_lowrey@xxxxxxxxx>]

I installed a transmission temp gauge on my 1997 Ford F250 today. It went 
rather smoothly, so I thought I would document the expirence so that others 
might know.

I purchased a B&M Transmission Temperature Gauge (Part #80212) from Summit 
Racing (http://store.summitracing.com). I used their web site to order, and 
it arrived via FedX Home the next day. They also included some kewl "Summit 
Racing" decals for my truck :-)

The kit consists of a round lighted temperature gauge, a case for the 
gauge, T-Fittings (both 3/" inch and 5/16"), sender unit, wire, eye and 
spade terminals, nuts, washers and instructions.

The T-Fittings are standard brass compression fittings. You cut the return 
line from the transmission fluid cooler, and insert the fitting in-line to 
it. The sender unit goes into the "leg" of the "T". While the instructions 
say you CAN use a hack saw to cut the line, I STRONGLY suggest you purchase 
a "mini" pipe cutter. They carry them at hardware stores, in the plumbing 
section. They dont cost very much, and are handy in tight spaces, like by a 
transmission :-) It you DO use a hacksaw, you will have a heck of a time 
getting the compression fitting on.

The instructions tell how to identify which line to cut for most GM and 
Ford transmissions.

Be sure to make sure the section of pipe you install the fitting in is 
grounded, and not in between rubber hoses. Use a meter and check. If it 
isnt grounded, you will need to run a wire from the fitting to a frame bolt.

While the instructions say to use thread sealer on the fitting, I found 
that I had to use Teflon tape on the one the sender unit was screwed into, 
as transmission fluid continued to seep out no matter how tight I got it. 
Once I took it apart and used the Teflon tape, I was fine.

Once the fitting is in place, you attach a wire to the sender unit and 
route it into the truck cab. In my '97 F250, there is a rubber plug in the 
firewall right next to the spot the accelerator cable comes through. I just 
removed the plug, and the inside insulation mat plug behind it, ran the 
wire through, and re-inserted the plugs.

The meter requires 12V power, a ground, and a connection to your truck's 
instrument panel light circuit. I managed to get all three from the brake 
controller harness. Im not sure if all trucks have instrument panel light 
circuits there, but it certainly was handy! The only problem with this 
setup is that the 12V is always on. I plan to either find an accessory 
circuit wire, or install a switch to the side of the gauge housing. Altho I 
doubt that the gauge will wear my battery down very quickly...

The only real hassle was installing the gauge housing. I chose to install 
it next to the brake controller, which is by my right leg. Drilling holes 
and getting screws in there would have been extremely awkward, so I am 
using double sticky foam tape. We shall see how long that lasts.....

If you have room, you can also install the gauge in your dashboard. It 
requires a 2 1/16" hole.

If anyone has any questions, or suggestions on improving this process, feel 
free to drop me a line.

Dave