Hey all - after replacing 100% of the cooling system on my 95 4.0 AX15 and it still overheating at speed I gave up and took it to the shop. They figured out my brand new NAPA fan clutch was bad, but also that the gauge was reading high even though all the sending units were good. They haven't been able to find a replacement temp gauge, Mopar #83504461, so I just tried in all the usual places and struck out too. Any chance I can replace it with an aftermarket temp gauge in the same location, etc? I'd really rather keep it simple and stock-looking since the interior is really nice and I don't want to start bolting stuff on everywhere unless I have to. Any easy solutions for this?

Thanks a lot!

 

* Junkyard gauge, or advert on the wanted on this site, they get wrecked,

* aftermarket gauges are easy, just need to find out thread size and maybe an adaptor,

In addition you need to know if a '95 coolant temp sensor serves any other engine control purpose apart from feeding the gauge, the senders changed a bit over the years

Others will know the answer to that and the thread size

 

I would not trust the shop just yet. You need a simple decade/ resistance box. It allows you to input variable resistances into the systems to check the outputs. I found one on amazon for 18 bucks. Your gauge should output around 210 for an input resistance of 675-700 so get the resistance box and set to those resistances...since you have an ohmmeter, you can check accuracy of resistance box. You need alligator clips and hook up the resistance box to the terminal on the temp connector and the other one to ground. . The shop does know that the temp gauge runs off the small sensor at the back of the block right? High resistance reads low, and low resistance reads high. turn on the jeep and see what the temp gauge reads. I find it difficult to believe the napa fan clutch was bad. Acxico is the name of the resistor box

 

Thanks for the replies, awg and bluejeep. Actually the shop did test all the wiring and sensors to be sure it was the gauge, and then hooked up a different gauge and it read perfectly. But, I didn't know about resistance boxes, and I'll definitely pick one up so I can test other stuff myself in the future.

AWG, I had no idea an aftermarket gauge would thread in - you learn something every day! Any chance it would install in the same location, or do I need to run it somewhere else?

Thanks all!

 

[QUOTE=
AWG, I had no idea an aftermarket gauge would thread in - you learn something every day! Any chance it would install in the same location, or do I need to run it somewhere else?

Thanks all![/QUOTE]

Maybe it will, maybe not, you need to know the thread size and count...and coolant sensors cannot be used with an adaptor, as it makes them innacurate

A used gauge is the way to go imo, (if it is a faulty gauge). I see stuff like that on Ebay all the time, cheap as dirt, you may have to pay for a whole cluster

keeping things original makes sense

 

I have these charts for the other gauges if anyone wants them.

 

Hey all - many thanks for all the good help. I ended up finding a used instrument cluster for $60 on Ebay, swapped out the temp gauge, and same thing - looks like the shop was wrong But now I have a backup cluster and these parts aren't getting any newer. Turns out it was the temp sending unit; even though I tried several from the parts stores, they're all apparently known to be garbage. Got a factory one and finally reading accurately!