Peterbilt 379 1999 gauge issue

Ck the ground wires on the rear mends and there should b two wires to the oil temp one is ground as well
Check all ur fuses in fuse box make sure there all good
That will b a starting point
On the pyro ck to make sure the two wires that run it have good connection were thy connect by the turbo in the exhaust two little bolts with nuts that conect them wires tougher sometimes get lose

 

That dif light on and abs light
Abs light put peace of tape over it
Dif light I'd flip the dif switch if it goes out in the locked Position I'd pull air line lose at front rear end by the drive shaft see it has air to it with the switch in the unlocked position Someone mite of got the lines crossed
Ck and drain all ur air tanks for water

 

On the ABS light don't tape it, take the bulb out easier solution, my dash is the same as yours if they pull you over tell them you put a 92 or so replacement panel in...no abs light in those and they're about 100 in a junk yard as opposed to 350 from pete.

the rear and front driver oil temps aren't really needed right along with the trans temp many times they cause more harm than good, my rear driver will read 300 in the winter from a short, it's cool to the touch along with the hubs so no worries,

as josh said on the pyro check the wiring first, the combo isn't cheap and I'd always buy a combo instead of just doing the probe or the gauge.

engine oil temp isn't a huge deal either they're more so added gauges that most trucks don't have I'd do a little at a time if you insist on replacing them the abs light and diff are the ones you want to get taken care of the soonest. ABS is a rather large fine if you're caught which is why I took the bulb out of my tractor, rear ends aren't cheap and if by chance soembody has flipped things around and it's locked in on dry pavement it's harder than hell on the rearends and 3rd members are around 2500/rear last time I checked.

 

Take temp gauge hot wire to ground. If gauge goes up its the sender.

 

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