Sounds right. So evidently the books don't match their web site. Didn't see "max cooling" mentioned back then or now although I've definitely heard of it.. First time I ever saw 272310 it was listed for the 2.5's.

Just did the same for a '98 Jeep GC and got the same results as for a '96 one.

 

Well i cranked in a 2k Cherokee 2.5 into the NAPA website.
What do you know, it says it fits!

The NAPA parts guy got that right at least according to his official NAPA parts data base.
But he got it wrong for a '99 4.0 according to their public website.

This is getting interestingliyer and interestinglyer.
I have a hard time believing a 2k 2.5 has a bigger cooling problem than a 2k 4.0
Unless the 2.5's came stock with a cheesier radiator or something.
Or
NAPA is totally screwed up with the clutch fitments.

 

The guy at O'rielly who searched only the part number without putting in vehicle info said that the clutch was for the 2.5 liter and the YJ 4.0 (or TJ. It was a while ago) engines because the YJ didn't use an additional e-fan. My dad has a 95 ZJ with the V8 but his m-fan barely makes any noise. Anyone know why that is? Seems like the tighter space inside the engine bay of an xj leads to more turbulent wind (which creates the noise). Also, i was looking at water pumps on the Summit website for the XJ and there was the flowkool or whatever it's called w/p for $100+ but under it another w/p for $50-60 ish that is an upgrade over stock but uses similar impeller design to the stock w/p other than the flowkool one which uses the turbine impeller (right?). Therefore I believe that the $50 w/p won't move the coolant too fast that it doesn't cool but fast enough so it theoretically improves hp (probably only 5 hp at most) and if it does overcool or move the coolant too fast to cool, you can probably just install something to reduce the flow rate.

 

The specs I posted are for NAPA part number 272310, which is not an XJ clutch.

 

Does the AC fan come on when AC is off and temp is high? If not, you could wire in a switch to turn it on either manually or using a temp switch automatically.

 

Maybe in their books it's not.

https://www.napaonline.com/en/p/TEM272310

Scroll down and click on "buyers guide".

 

I stand corrected...

However, if you look it up in reverse (choose vehicle first), it isn't listed as an XJ clutch. What I have stated above about that clutch is just from years of reading the forums (that it is a ZJ clutch). I don't have any first-hand experience with the part.

 

XJ Upgraded HD Fan Clutch-
Hayden #2737 Amazon $41 free ship have used on 3 different Jeeps
NAPA #272310 $43 quoted by many user, no personal experience, ?loud

 

That one cross-references to a 2.5L XJ as well. I suppose I'm wrong about the ZJ thing. These both appear to be for that application, as stated by moparado.

 

Tbone you don't need to be corrected. NAPA's web site has some issues. I just chose a '98 GC as my vehicle. Typed in part #272310 for the part # and it shows 5 options. All 272310's. Typed in fan clutch for the same vehicle and got 2 options with different #'s but neither are 272310.

What I do with any parts store is get the part # online then have it double checked at the store plus match it to my old part before buying it. Never had a mismatch but doesn't hurt to play it safe.

 

It is all a bit mysterious, isn't it?

I usually do my own research before I hit the parts store as well, but this one still would have been pretty confusing.

 

If thats true, that some years/engines/Jeep models didn't come stock with an efan then this could start making at least a little more sense.

Are you saying that if the flow rate is high enough, it could counter act the thermostats ability to close causing over cooling?
Anything is possible i suppose.

Could be wrong, but I would think its improbable to over cool if the thermostat can close properly and with the right type of thermostat.
And maybe the lesser time the hot coolant spends in the radiator to cool down.
The temp fluctuations might be a little more radical due an increased flow rate.

Hell i don't know for sure, just putting some unproven theories out there for comments.

 

That's a theory out there on the internet. Maybe in some race car or SBC application but I've never seen it happen on a Jeep.
I call it 'Jeep Internet BS'.

Having said that, I always run a thermostat.

 

Wasn't referring to running without a thermostat if thats what you meant.

I was referring to a greater coolant flow velocity from a souped up pump which might have the effect of the coolant spending less time in the radiator when the thermostat's valve is open.
Whether that could be true or have little to no affect on cooling, i don't know, just threw that out there.

Like you said, i also would never run my Jeep without a thermostat no matter what kind of pump, stock or a souped up one.

 

Remember to that increased flow rate means less time the coolant stays in the engine to absorb heat from it.