Flex Fan Fan.

[Panelman55]

Yes I've been a flex fan fan for many years. I have "00" Silverado with 5.3l and was getting ready to replace the water pump at 160k miles. Thought about tossing the fan and clutch and installing a flex fan like we did on the older chevys back in the day. I did a search and found "0" on the subject. If you have a comment on the subject let me know. Thanks in advance.


Panelman55

[clinebarger]

Flex Fans are an EMERGENCY measure ONLY. In fact they only suppose to be used so many miles.

[Panelman55]

Okay so where did you get that information? I installed and ran one a 454 for regular street use for 200k miles never had any problems with it and no cooling problem. I've never heard not to run them for long periods of time.


Panelman55

[clinebarger]

I got that information right off the box of a flex fan. It's for your own good that nobody makes a Flex Fan for your truck.

[truckdude239]

Flex fans are danrous i had a friend install a new one and it flew apart after about 30 miles trying to get home came right though yhe hood

[imjeff]

Panelman, I don't think they make the flex fan replacements like they used to. The fan/clutch technology has come a long way and there really isn't an advantage anymore. I have ran the old ones back when the stock fan sucked big horsepower, too.

[studda]

I have one on my '68 GTO clone that was a daily driver for 2 years and it's 350hp+ 406 inch big block pushing it over 5500 rpm. No problems with overheating or it flying apart. I used to run one on my '80 K10 daily driver too that had a crate 350 in it with powdered metal rods. I revved that thing like crazy and never had failure. I've never had problems with them. I'm not saying they would necessarily be better than the stock fan, because I just don't know. I just don't know that they are that flimsy. It's probably more for a liability reason that they put that on the box.

[onebad65c10]

Panelman, another alternative could be to find a set of electric fans off a later model. My 05 has dual electric fans. It would just be a matter of installing the sending unit and wiring them up. If you have a pick it yourself junkyard around you it could be a pretty inexpensive upgrade. I have done to a few friends early model trucks and suvs. Also this aids in quicker warm ups on cold days. Just make sure that your factory radiator has the mounting tabs for the fan. Just my $0.02.

[Panelman55]

Thanks for the input guys, I was just asking for information's sake. If an electric fan set up will be better, that might be the way to go. I want to take out the fan clutch, as i think it is a weak point and robs power. I thank you all for the input.

Panelman55

[studda]

You can get an electric fan from summitracing for a decent price. You can get ones that are universal or ones that are specifically for your truck.

[texasag91]

Panelman55,

I just put a new flex fan on my truck a few days ago. It wasn't till after I had ordered and quick shipped it that I found a few threads on this site that were discussing how good or bad the fans were. Like most of the threads that I read most people were saying how the would throw blade and through hoods. Most of the people saying this were like " Yeah, I heard they went through hoods" "Yeah I had a friend of friend of a cousin of his that had one go through the hood or radiator." Never really got some good answers.

Well the reason I had to get a new fan was because the "Factory OEM" threw a blade and almost went through the hood. So it can happen to either.

I was going to start my own thread but I think I will post it here. I will keep everyone up to date how it goes and if any problems.

My truck: 1990 GMC Sierra V3500 Crew Cab 4x4. TBI - 454, Hooker headers, Elderbrock intake.

New clutch Flex Fan - 19" installed with 1" spacer/No clutch istallation.

My thoughts: Only a few days on my truck.

Cooling - Not much difference than the OEM. Maybe runs a little hotter than OEM/Clutch Fan while parked. Runs about 210 while parked (Daytime). Runs about 195-200 at 70-75 mph (Daytime). Runs about 200 at 70-75 mph (Nightime). Now this is in South Texas summer heat. This is all based on daytime temps right at 100 degrees and nights right now are about 77-80 degrees for a low. Oh and 80-90 degree humidity. I think the fan is doing pretty damn good for the engine and the outside temps.

Noise - I just bought the truck about 2 weeks ago so I think the old fan blade was making a little extra noise before it threw the stock blade. It is quieter than before. I really can't give you a true reading on the sound but I don't think there is much difference.

The problems some people posted about the over heating and running hot in opinion is on how people might set up their flex fans. If you were running a 19" fan before you have to run a 19" flex fan. Don't go any smaller. Also, I had to buy a spacer the compensate for the lose of the clutch fan. I used the 1" for mine. Probably could have gone to the 2" but I had to hurry and order late on Friday to get it out for shipping so it would arrive on Monday. Only made a quick measurement from water pump to radiator. After installing looks like the 2" would work. The instructions on box said no closer than 1" from radiator. For the fan blade to work properly you have to have it within the fan shroud to direct air right to the radiator. Read up on proper install instructions before you buy one.

I just got to thinking about this right now and not when I ordered. I guess the flex could have possibilities of throwing blades in time if the aluminum fans blades start wallering out around the rivets. I think mine was well made or I would not have put it on my truck.

All this is based on being a new owner of a new flex fan. I will post in time if I have any problems. This is test of a new product for me on my ride. Guess we all learn by trial and error.

Hope this helps someone in the future if they are deciding if they want to buy a new flex fan.