TJPro351

I installed a hot line with a sender unit. My gauge only reads 100 degrees. Thinking it was a sender unit, got another one from diesel manor. It still only read up to 100 degrees. I got a replacement gauge and it still does the same thing!!
When I installed all my gauges, I checked and rechecked 12v line and the grounds. I checked the ground for the sender unit again. One proble on the outside of sender and the other probe in the cooler. Got a good ground Well, I decide to check another source for ground (tranny case) and I got nothing!! Ran a wire from the neg terminal, one probe end to terminal and other to tranny case....good ground.
For some reason, the cooler is not frame grounded?? I cannot get a good ground from cooler to tranny case or anything else. That has to be my reason my tranny gauge is not working.
Ran out of daylight to try to wrap a wire around the outside of sender unit to terminal ground. I will try that tomorrow to see if my gauge will work.
Has anybody run into this using a hot line for tranny gauge??? What am I missing here?? It is hard to beleive the cooler is not grounded to frame. Gotta be bolted somewhere

Running out of ideas...can anybody help?

TJ

pullin hard

i take it the sender has 2 wires coming from it?????
i have a tranny gauge that has never moved since the day i put it in the truck. it just doesn't work.
mine are the isspro gauges, and the sender has 2 wires. i thought maybe because my tranny pan is cast aluminum, it wasn't getting a ground, but i don't know for sure.i am switching to autometer gauges anyway, and their sender only has one wire.

TJPro351

I should have identified what kind of guage I have. It is a Dipricol Tranny gauge with one wire going to sender and ground wire tied in with pryo gauge thru the harness going to ground bolt underneath above go pedal.. I am assuming the outer case of sender unit is case ground. It has to ground somewhere at the sender unit.

Spooler

I installed the ISSOPRO gauge. The sender is not grounded to the truck ground. Both wires go to the gauges amp box. You should have a 12volt supply, ground, 2 sender wires, and 3 gauge wires(I think from what I remember.)

pullin hard

sounds right, but for some reason, i don't get good strong 12 volts from the amp box to the gauge.
if the one wire senders are grounding to the pan, not sure how that will work with the cast pans, or the rubber gasket.
i think the 1 wire just reads signal to the gauge and the gauge should have 12 volt postive, and ground, same for the lights and a sender tab.
as for your problem TJpro351, maybe got a bad sender. maybe try to pull the sender out, plug the hole which it came from , and try to heat it up a little with one of them butane lighters or some thing to see if it moves the gauge.
worth a try anyway.

roger/dodger

I have this same gauge in my truck but it is installed in the Mass Diesel custom line. Where it sets is between two pieces of rubber hose, I don't see how it does ground. And I don't think it has to on the sender end. You may not believe this but I think your hook up is fine, it's just it takes a lot of stress on the oil to raise the temp up off the 100 degree mark. Once the tranny is in lock up even at 40 mph there is little friction to heat the oil. I thought mine was broke also, It has ben only about 65 degrees here in Tucson and the gauge sat there for two days on the 100 degree mark. Then after driving a while. I did three burn outs, 1500 rpm pre load on the tranny and a lot of rubber latter and the gauge jumped to 150 degrees ! Then the other day it finally got to 88 degrees and the gauge was at 160 in normal driving.

TJPro351

I have tried two senders and two gauges. Its got to be bad ground. Again, the outer part of sender has a good ground going to the cooler. But the cooler does not ground to frame. I am gonna run a direct ground from the sender to frame ground and see if that makes a difference.
The outside temps has been around 85. If the gauge is working right, I would think it should read about 30-40 degrees higher...no?
You say you connect to the amp box? I thought the amp box was for the pyro gauge??? My tranny gauge wire goes directly to sender and from the harness, has a black wire for ground. And two other wires for lighting.

Badd Dogg Guy19

I have an 87 IROC with a strong 355 in it with a proff, built race trans, with a 10 inch Art Carr converter. When I had this all put together, I installed a trans temp gauge. I can relate to these guys on here that say the gauge can sit on 100 deg. all day. I can take a 2 hour highway ride with my car, and the trans gauge will stay at like 100 deg if im just cruising. The min. I start romping on the car, or shift it manually, the gauge will start rising pretty quick. Ive driven the car on 95 deg. days, and when I baby it, or just drive it narmal, gauge still reads low, but the min. you start working the trans, thats when things heat up.

I would really think twice if two. possibaly 3 gauges went bad, I do have Autometers in my car, if that helps, but what the guys on here are saying about how the trans gauge can stay low all day long is true.

Capp35

Isspro gauges don't need to be grounded.

You need to get a replacement out-going fluid line (like Mass Diesel) that has a port for the sensor. You will notice quite a bit of movement in the gauge.

TJPro351

All gauges need to be grounded one way or another. I believe Isspro Tranny gauge don't need to be grounded is because they have two wires going to sender, one for voltage and other ground.
I do have a hot line that supports a sender unit. Read above

67Charger383HP

The gauge has provision for 12 volt and ground as well as + and - for lighting (if you are talking about a Optix gauge otherwise this wont help) The sender wire should peg the needle of the gauge full hot when it is grounded out.

Good luck.

Capp35

Ok....
let me rephrase that. The sensor itself does not have to be grounded on the transmission.
There are two wires on the sensor going back to the box. In fact I had to lengthen mine some.

You can take the sensor out of the transmission and put a cig lighter on it to test it.

If you do not have it in the transmission line though, you will not get accurate readings.

TJPro351

I agree with you. On the sender with 2 wires (one ground, one voltage), it does not have to be grounded to the hot line or tranny pan. But with only one wire (voltage) the sender has to be case/frame grounded.

As I said before when I installed my tranny gauge, I checked and rechecked the sender unit ground to cooler. I knew I had a good connection from the sender through the tube to cooler unit. The gauge still did not work even after getting a new sender unit and gauge. So I went back under the truck and checked for ground again. Again, good ground from sender to cooler. Then I decided to go from sender to tranny case.....no ground. Then ran a wire directly from NEG term to one end of meter and other probe on meter to sender..>NOTHING. I took a hose clamp and some long wire. Cramped an eye terminal at sender end and put in the little slots on the hose clamp. I then tighten the hose clamp on the sender unit compressing the eye terminal against the sender. Ran the wire in the same bundle as voltage wire for sender and and cramped on another terminal and grounded it to a existing ground terminal block inside motor compartment on drivers side.
Low and behold, the gauge is NOW working. I don't understand why the cooler is not frame grounded. If it is (no rubber washers between mounting bolts), it must have lots of resistant with the alumimun.
My buddy also has a 06 Auto CTD and his cooler does not ground to frame either.

So, if you use one wire sender unit using a hot line, make sure your cooler is frame grounded. If not, then do like I did.

Hope this helps all the ones that never got their tranny gauge working

Capp35

My bad.
I saw from the first post, you bought from Diesel Manor. They specalize in Isspro gauges and those don't need to be grounded.

Didn't read in the next post, you bought Dipricol.

Herrin811

Took some digging but found this thread....I have the same problem...Optix wont read over 100'.....