ok so my fuel gauge is off. basically when the gauge reads 1/4 tank it is actually empty. so i ordered a new sending unit from rock auto. and the new one from rock auto only has 1 electrical lead coming out of the top of the sending unit plus a ground wire. but i dropped the tank and the original one has 2 electrical leads coming out of the top plus a ground wire also. ive checked the parts numbers and the new one matches what should be on the vehicle. my question is can i wire the new one with only the one leadout to work properly? or what?

 

You did not post a model! I had to chase your old posts to find an 1983 98.

Any way Rock auto shows su171 or su170, ran both of those numbers on the net and came to Shepard auto part web site and put you vehicle in and according to their website neither one fits the 5.7 Diesel option for your car.
I also ran your car through Napa,AZ and Adv and big fat zero!
Suggest that you send your old sender to Bobs speedometer in Howell MI.

Pat