CK5
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I have an ok stereo, but my single muffler is 3" inlet and outlet, 15" x 6" oval 28" long so I would hear the fan.
 
Just a stupid idea here, but is the electric fan blocking or disrupting airflow on the highway? If it is on at all times with the A/C, I have heard that airflow at higher speeds can suffer if the fan is on. I have no personal experience with this though.
Could you disconnect the fan and try to see if there is any difference at all?

Now what I DO know, is that my Edelbrock water pumps work well. Pricey, yes. But both of my old trucks have good cooling.
My LS1 fans (only one of which comes on under normal conditions) will drive engine temps down at freeway speeds, so they definitely "work" at freeway speeds. I suppose it's possible with more blades and less space between, they might be a hindrance to airflow vs the big metal fan, but even some of the stock fans had pretty tightly spaced blades IIRC.

I've said it before, I don't think air flows through the engine bay like most of us think/thought it did at speed. Look how small the core support opening is, compared to the size of the front end. The radiator is quite a bit bigger than the cutout in the core support, which if that is all we look at, would make it seem like there is a larger path for airflow than there really is.

I'm theorizing that at freeway speeds, the small opening in a big front end that has almost zero aerodynamics, leads to "spoiled air", that the fan helps direct. I don't know at what vehicle speed things change, but from what I've seen up to about 65MPH, fans work.

I have driven around without fans before just to see, and on flat ground, unloaded, at 25-40MPH, fans were unnecessary. But that is not the same engine load as moving at 65MPH, pulling a grade, etc.
 
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Yes, obviously the load on the engine is different, but lots of things can change at different speeds. And and there are differences in vehicles, fans and such. My point is try different things to see if anything at all leads to a clue as to what's the problem, or problems, are.
I have found seen a lot of systems where the the A/C uses a pressure switch to turn on the engine fan, it isn't always just turned on with the A/C clutch. And when in front of a mechanical fan, which could possibly have fan to shroud restrictions, the electric fan in front may be causing a restriction at higher speeds. As I said, I have heard of this problem, no real experience myself.

I did have a twin electric fan set that didn't seem to work properly in high wind and speeds above 55 mph. After going to mechanical fan and electric pusher, the pusher fan doesn't do much. Neither the engine temperature or trianary switch turn it on once moving over 15 mph. But that is a different truck than what Wes has.
 
I am telling you guys until he puts the fan halfway in the shroud all this is not getting him anything.
I have been there, the fan is not able to pull the air properly out of the shroud it just throws it around in the shroud.
That should be his priority.
 
@imiceman44 no short clutch available local. I'll see if I can shim the fan blade back.
Only thing that puzzles me, this shroud and fan blade have been on the truck as long as I have had it. Now I did change the clutch a few months ago, while I won't swear they are the same length, I normally compare those things b4 I installed.
 
I am telling you guys until he puts the fan halfway in the shroud all this is not getting him anything.
I have been there, the fan is not able to pull the air properly out of the shroud it just throws it around in the shroud.
That should be his priority.
Meanwhile, my black '90 will go wheeling in Moab, 98* heat, with the A/C on and the fan is too deep into the shroud and it doesn't get hot.
I believe that there are several factors at play here.
 
Any possibility you're running lean?
Unknown a/f. Can't read plugs with this crappy gas we have. No wideband.
The qjet has 69 main jets, I tried 71's they would load up at idle on a long light, and make your eyes water. So I went back to 69. 39B rods. I have the big orifice inlet seat installed. Next stronger spring in the main metering rod piston. The float level started at highest published setting I have dropped 2x now 1/32 at time.
Vacuum leak, haven't checked in few months, idle hasn't changed since last adjustments.
Here is a picture of fan in the shroud.

20210518_113410_Film1.jpg
 
Have you checked to see if the clutch is good? Fan clutch testing

Some of the statements there conflict with what I've seen, but that may be aftermarket differences, etc. Any fan clutch I've messed with that is good has resistance to spinning even when cold, that is easily felt. On startup you can tell they are locked up by the sound and air movement, after a few seconds it will quiet down if the engine is still cold.

Any bad clutch I've seen, spun freely by hand.

How about your water pump? Unknown quantity/condition? If the radiator was rotten, the water pump, unless new, was exposed to the same conditions, and it is possible for the pump vanes to rot.
 
Well I checked the fan clutch yesterday. It has mild resistance cold, I can't hear it change much. but it is running locked up 90% of the time by design.
https://www.haydenauto.com/en/ecata...Rotation Thermal Heavy Duty Fan Clutch&type=p
when I shut the motor off fan stops dead no free wheel when hot.

Water pump is 20ish years old, new when I built the motor. 8 years of non use. I suppose it could have impeller issues. Radiator was older than water pump. Now I have always had 50/50 with distilled water in this engine. when I flushed in April it was pretty clean not a lot of crud. I drained coolant in to a clean bucket on Saturday for t stat swap. I put that coolant back in, i mean April. Coffee filer in a funnel with a screen, the debris left in the filter was nothing hardly.
Tip, 500ml water bottle, cut a hole on the side close to bottom, put that hole over petcock with cap side pointed down over the top left of steering box will drain in 5gl buck no problem no mess.
I just tested again after retarding the timing ever so slightly, shifts better, but still runs @ 5/8ths on the gauge no A/C, 99 degree ambient. Going to remove a little more timing and try again.
Can't move the fan right now all of my resources are in other garages in another state or tied up in escrow, I'll say Amerisave mortgage company, is horrible they keep asking for the same documents over and over again even thou we provided them. Bunch of F'n idiots.
 
I used the Gearhead app and found it’s the same RPM range on mine
Well Bent I think I figured out the vibration, Tcase was in 4wd hi. After carpet install I never checked, and no indicator. I don't have the front shaft in atm. reminds me I need to see if Kenny or Ron have a 205 indicator.
Got to get it out on the highway for long stretch to be certain.
 
Seems pretty unlikely the pump is rotten then as long as the antifreeze was changed at whatever interval is recommended by the manufacturer. Could be I suppose, but not like it's an easy check.

Like the water bottle idea!
 
@Bent77 vibration is still there wasn't the t case, thou it was contributing.
Left AZ today 5:30 pm 90 degrees plus, temp stayed right on the center line up hill, down hill, flat, No A/C for the trip. Wind was bad, and once I got into the high desert outside temp drop 30 degrees. traffic was good made 200 miles in 2 hours 40 minutes.
 
Could be I put air soft bb's in these tires, the 1st time I have tried this. Time to rotate. I am going to do the go pro thing and see what the pinion angle is doing. feels like the rear. comes back at @3600 rpm in 3rd.
 
what do the air soft BB's do?
Could be I put air soft bb's in these tires, the 1st time I have tried this. Time to rotate. I am going to do the go pro thing and see what the pinion angle is doing. feels like the rear. comes back at @3600 rpm in 3rd
 
If you get enough of them, it’s supposed to internally balance the tires. I use double B shot in mine
 
So I ordered some front tuff country springs from ORD Ez rides 18470. They arrived while I was in Lake Havasu, I just got a chance to check them out. I received 18471's HD springs not the ez ride. So since I order from ORD and they know is for a 3/4 ton suburban did they order the HD be cause it's what I need and not what I wanted ?
 
Not really their style, they tell you on the phone. Give them a call tomorrow and discuss what you see
 

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