How do you know what gears you have? 1993 6.5 turbo with automatic 4x4 heavy duty.

[nealpellecchia]

Rear end of course.

 

[NVW]

Generally 2200 rpm at 65 mph are 4.10, 1800 rpm are 3.73 gears.

 

[nealpellecchia]

2,000 at 57mph. Approximate.

 

[NVW]

Sounds like 4.10

 

[nealpellecchia]

How much does high ambient temp affect water temp guage ?

 

[nealpellecchia]

Hot air hitting the rad?

 

[nealpellecchia]

Once thermostat is open hot and it's getting hotter it stays open and the car will get hotter as the weather gets hotter, right?

 

[FellowTraveler]

What transmission and is it in O/D @ 50 mph or?
What tire size?

 

[nealpellecchia]

4l80e in overdrive 245 75 16

 

[nealpellecchia]

4l80e in overdrive 245 75 16

57ish. 2,000 rpm.

 

[FellowTraveler]

57ish. 2,000 rpm.

Your looking at 4.10 with vssb slightly out of calibration or perhaps just tire wear......

 

[nealpellecchia]

Thank-you.

 

[Will L.]

How much does high ambient temp affect water temp guage ?

Massive impact.

In nice cool weather, under 70f and over 10% humidity, I have to tow something to get my rig hot, otherwise I can push it as hard as I want and it will not hit 210.

Currently over 110f almost nothing I do can keep it from overheating over 55 mph towing nothing.

 

[nealpellecchia]

At 100°f I did 55 mph and kept it at 195.

 

[Big T]

Rear end of course.

Read the RPO codes on the sticker located on the glove box door. GP5 = 4.10, GP4 = 3.73.

 

[nealpellecchia]

Cool.

 

[Will L.]

It no rpo sticker- you can always jack up the rear axle and count rotation of driveshaft and tires. Then do the math.

 

[Big T]

It no rpo sticker- you can always jack up the rear axle and count rotation of driveshaft and tires. Then do the math.

Way too complicated. Aren't the RPO codes stamped on top of the axle? GMT 800 models have a bar code label on the axle.

 

[FellowTraveler]

Already, did the math see post #11

 

[nealpellecchia]

Read the RPO codes on the sticker located on the glove box door. GP5 = 4.10, GP4 = 3.73.

I saw a GT5. List of options right? 1993