Normal temp stock engine.

[Warrennc]

I am assuming a few things with my new to me 1995 F350 7.3 ps.
The dash temp gauge failed before I got the truck. The PO installed a mechanical temp gauge and mounted it on the floor. Hard to read down there so I had it replaced, moved to the piller. New mechanical temp gauge.
The other day I finally had a moderate road trip. Only about an hour each way on contry roads and running empty.
Speeds averaging 50 to 55 empty, standard trans. The engine runs about 150 degrees at the gauge.
When I get into town and slow down, it drops to about 140 degrees.
I'm familure with gassers running about 200 all the time. But this is my first diesel.
Is this normal for a stock 7.3 engine? Or is this a symptom of a failed, not closing, thermostat or something like that?

It has been suggested i replace the thermostat with a 203 degree thermostat but there is some question as to if I need a short stem or long stem and if my water pump is original stock or replaced and if replaced did they use a slightly different pump that can take the long stem.....etc...confusing. May have to leave that up to my diesel mechanic I use.

[BigFuel]

The OBS Diesel does run cool. We have HUGE radiators for when the truck is loaded down. When you bought the new gauge did you install the new sending unit or did you use the old one?

[Warrennc]

Originally Posted by BigFuel

The OBS Diesel does run cool. We have HUGE radiators for when the truck is loaded down. When you bought the new gauge did you install the new sending unit or did you use the old one?

I will have to ask the owner of the shop that did the work.
I didn't do the work my self. Don't have a lot of spare time to fix things my self.
As for the gauge. it is mechanical. I presume Sender is for electrical gauges not mechanical?
I would think it would include the sender due to it being a complete gauge and connecting tube.
I will ask this evening on my way home from work if they are still open.

Thanks.

[Warrennc]

He was open. Yah, when installing a new mechanical temp gauge, it includes everything and a mechanical gauge doesn't have a sender like an electrical gauge does. So, it is new from where the sensor hits the water all the way to the gauge.