The factory doesn't waste time on unnecessary 'U's. Maybe they pioneered removing it from color and neighbor too. Waste of ink/electrons.

And I'm guessing that meant it had oil pressure and temp gauges (sorry gages) as opposed to the bare minimum dummy lights in 82.

 

U21= Oil Pressure,Cooling,voltage and Tach gauges

 

Exactly It's Standard Equipment Shouldn't Be Listed As A 149.00 Option

 

Does your RPM tach redline at 5500 or 4500 I’m curious because that RPO code is for the Firebird’s also, just wondering if that’s the code for 5500 because mine redlines at 5500

 

The instrument cluster RPO code does not directly specify the tachometer range. It merely defines the different types of clusters (warning lights, full set of gauges or digital cluster).

 

Yea, I’m trying to decipher this page

 

5000 mantaguy

 

That's a 5500 redline.

I'm not sure I understand what there is to decipher? The RPO codes simply designate the type (base gauges with warning lights, optional gauges or digital cluster) while the part number itself designates the tach (redline) and speed measurements/distances (mph/kph). As you can see, the U21 applies for a wide range of applications but has different part numbers for a specific "calibration".

 

why different RPO codes were not used for speedometers that read (85 -120 MPH) and Tachs that Redline at 4500.They use the same as the 140 speedometer and 5500 redline RPM

 

Because they have different part numbers.

 

I never even thought about that