Bad Fan Clutch? If so, which is the right one?

[1993GMCSierra]

Hi all,


Flushed the cooling system in the truck today, and noticed when "burping" the system I suddenly had no cold A/C at idle, and the engine temp was ever-so-slowly climbing. The radiator fan wasn't spinning, but I didn't worry as the engine was still cooler at the time, figured it wasn't hot enough to kick in. Long story short, I didn't put the rad. hose back on right, and instead of it resting on the upper edge of the fan shroud, it was ever so lightly resting on the fan blades, keeping them from turning.


When I pulled the hose away, it took the fan blade a good few minutes to catch up to speed.

I'd assume, when working properly, the fan would have shredded the radiator hose. I'm thinking my fan clutch is shot, once it finally got up to speed, A/C was working well at idle.

Looking at Rockauto, there are tons of choices.

Just looking at the AC Delco ones, there are Delco # 154553, 154536, and 1580278.

154553 {#22149568}
CLUTCH,FAN BLADE CODE DD,GG,GN

1580278 {#19189693, 89000195}
CLUTCH,FAN BLADE REGULAR CAB; 4 WHEEL DRIVE; REVERSE ROTATION STANDARD DUTY THERMAL FAN CLUTCH, 3.42 OR LOWER RR AXLE RATIO; w/o A/C MAN CONT(C60)

154536 {#22124529}
CLUTCH,FAN BLADE w/3.73R(GT4) or 4.10R(GT5) or ENG OIL CLG(KC4); CODE BT,GM,HL; w/o A/C MAN CONT(C60) or HVY DUTY RAD(V01) or HVY DUTY RAD & TRANS OIL CLR(V02) (Only 5 Remaining)



What numbers on the build sticker equate to what rear axle ratio? I don't want to buy the wrong one.

 

[1997chevydriver]

There is a good chance that with the truck stationary and the fan not moving at all there was no airflow thru the rad to warm up the fan clutch and have it lock in.

Your fan clutch is probably fine.

And with no air flow thats why your a/c wasn't working either