Worth doing blue hub fan clutch mod?

[nodaksn3]

The US clutches are filled with light weight fluid to goose gas mileage by .00001 MPG. The ones in the middle east likely have heavier fluid out of the box.

Hi Rob- Having spent some time over in Abu Dhabi and looked at a bunch of their cruisers I wonder if that's true. How do you know that?
Just askin'
Ned

 

[Rwhat]

Add 20k cst and get over it. You can't go wrong. I have done 4 clutches in the bay area and they all have a significant increase over stock fluid. The blue clutches drain fluid very fast. Heat up the. Lurch before you drain it so it thins the fluid and drains faster.

Spin your new clutch by hand and the. Spin it by hand with 20k cst fluid. I'll be back in Cali in a couple weeks. Stop by SJ with a 24 pack of rolling rock cans and I'll sap the fluid and install it for you. (I got a new blue clutch on hand for another mudder I can swap fluid before you come)

 

[BrotherRob]

Hi Rob- Having spent some time over in Abu Dhabi and looked at a bunch of their cruisers I wonder if that's true. How do you know that?
Just askin'
Ned

My bro did a lot of research before we started modding clutches. He found that the US spec clutches were filled with lightweight oil to pass US EPA standards. At the time, he researched the Aussie spec rigs and found that they came with the thicker oil for enhanced airflow. That was the basis for the clutch mods that we all discusses on this board.

I can't say what they use in the middle east, but it's probably not a safe assumption that it is an apples to apples comparison.

The summer heat here is very similar to the middle east. I put a brand new, unmodified blue hub in my rig in summer of 2005. It was immediately obvious that it was woefully inadequate anytime the temps broke 105.

 

[Tools R Us]

... It's an engineered system in my mind. I have never had any cooling system issues with OEM parts. Even in extreme heat.

Happy for you, but several others have not had the same experience, even when running factory parts from an approved vender.

 

[Otter]

Would you happen to know the differences between the two?

The green hub that is stock on the 3fe 80s is a 3 stage clutch. Basically, it has a lot more shearing area than the blue hub clutches. The more shearing area the thinner fluid you need. My green hub was just rebuilt by Tools r us with 12,500 fluid. The guys with the blue hub are using 25k and 30k to move the same amount of air.

Thanks to Tools for explaining the difference and rebuilding my clutch.

 

[Tools R Us]

Would you happen to know the differences between the two? The original one was a green hub and I purchased the blue hub because of all the comments here about it. I assumed it was a newer more upgraded version for the 1FZ-FE motor which would be better for the older, less hp 3FE. Anyway, all that matters now is that it works perfectly with the 15K cst fluid in it.

The original aqua/green hub in the FJ80 is the same design (other than mount spacing) as the FZJ80 black hub, good clutch, large shearing area, so strong. I haven't had a replacement apart, yet, likely will soon, so don't know if they have been neutered?

The new type 1FZ blue hub has been neutered, is weak, would be my last choice among 1FZ clutches. Unfortunately, it is the only new replacement offered/available.

The first 2 pix are the FJ80 aqua/green hub, note the full set of 5 shearing ridges. The last pic is a comparison of the old and new 1FZ blue hubs, the old type has all 5, the new type has been neutered down to 2. This makes it weaker with equal viscosity fluid, in our experience, regardless of fluid viscosity, it will never be as strong as an early clutch and will always use up the fluid faster.

 

[neatus]

The original aqua/green hub in the FJ80 is the same design (other than mount spacing) as the FZJ80 black hub, good clutch, large shearing area, so strong. I haven't had a replacement apart, yet, likely will soon, so don't know if they have been neutered?

The new type 1FZ blue hub has been neutered, is weak, would be my last choice among 1FZ clutches. Unfortunately, it is the only new replacement offered/available.

The first 2 pix are the FJ80 aqua/green hub, note the full set of 5 shearing ridges. The last pic is a comparison of the old and new 1FZ blue hubs, the old type has all 5, the new type has been neutered down to 2. This makes it weaker with equal viscosity fluid, in our experience, regardless of fluid viscosity, it will never be as strong as an early clutch and will always use up the fluid faster.

I have blue hub on the 96 I purchased...TRU, do you think replacing the fluid in mine would help keep the a/c cooler at low speeds? This AZ summer is hot and my a/c is properly charged but at low city stop and go driving the a/c is leaving something to be desired. Can I find an older heavier clutch like you show above and rebuild it?

 

[Tools R Us]

Yes, it will help, you have PM.

 

[jonheld]

Happy for you, but several others have not had the same experience, even when running factory parts from an approved vender.

Kevin, love the pictures. It gives a clear explanation of the clutch designs through the years. Also explains why my OEM system works so damn well. I suppose ANY clutch could potentially benefit from a boost in oil viscosity, but it's nice to know it's an OPTION for me based on climate, not a necessity. When it gets hot, my fan roars like a DC10 on takeoff.

 

[SUMMIT CRUISERS]

The original aqua/green hub in the FJ80 is the same design (other than mount spacing) as the FZJ80 black hub, good clutch, large shearing area, so strong. I haven't had a replacement apart, yet, likely will soon, so don't know if they have been neutered?

The new type 1FZ blue hub has been neutered, is weak, would be my last choice among 1FZ clutches. Unfortunately, it is the only new replacement offered/available.

The first 2 pix are the FJ80 aqua/green hub, note the full set of 5 shearing ridges. The last pic is a comparison of the old and new 1FZ blue hubs, the old type has all 5, the new type has been neutered down to 2. This makes it weaker with equal viscosity fluid, in our experience, regardless of fluid viscosity, it will never be as strong as an early clutch and will always use up the fluid faster.

Thanks for your reply. That explains a lot. I did notice when I originally filled the new clutch with 20K fluid, the clutch stayed locked up too long. At highway speeds the fan was still roaring and was starving the mighty 3FE of what power it has. Since changing it out to 15K, I have not had that problem. It's been working great.

 

[Tools R Us]

... When it gets hot, my fan roars like a DC10 on takeoff.

With 10-12.5k they really talk!

 

[Tools R Us]

Thanks for your reply. That explains a lot. I did notice when I originally filled the new clutch with 20K fluid, the clutch stayed locked up too long. At highway speeds the fan was still roaring and was starving the mighty 3FE of what power it has. Since changing it out to 15K, I have not had that problem. It's been working great.

Yep, it is best to experiment, tune it to your need. I prefer a bit extra, to allow for extra capacity in case of an :whoops:.

 

[lehn20]

Hmmm maybe you can help with mine as well? I like to do the 15000 cst
Just did a Big Bear run last weekend and the temp went from 190-220 when climbing up the mountain and 210-216 on the Black Diamond trail at White Mountain. Had to turn off AC several times.

Add 20k cst and get over it. You can't go wrong. I have done 4 clutches in the bay area and they all have a significant increase over stock fluid. The blue clutches drain fluid very fast. Heat up the. Lurch before you drain it so it thins the fluid and drains faster.

Spin your new clutch by hand and the. Spin it by hand with 20k cst fluid. I'll be back in Cali in a couple weeks. Stop by SJ with a 24 pack of rolling rock cans and I'll sap the fluid and install it for you. (I got a new blue clutch on hand for another mudder I can swap fluid before you come)

 

[bsmart82]

Is the 1fz stock clutch serviceable and if so, what fluid should I put in it?

 

[98 SNAKE EATER]

My original fan clutch was working fine, but I installed a new blue as a PM.

The only difference I've noticed is the initial start up roar

I guess it just doesn't get hot enough in Florida cause I've never had any temp issues, even fully loaded and pulling a trailer, so I never bothered to mod it

 

[Schwaz80]

How do you know if you have a blue hub fan clutch?

 

[98 SNAKE EATER]

How do you know if you have a blue hub fan clutch?

Original and new Blue hub replacement

 

[80t0ylc]

...........I guess it just doesn't get hot enough in Florida cause I've never had any temp issues, even fully loaded and pulling a trailer, so I never bothered to mod it

I don't believe you have many, if any, long grades in Florida. Even towing you may not notice much difference on relatively flat ground. It's when the 1FZ has to struggle to maintain speed that you notice the engine temp climb, at least in my experience. And as most of us know, our engines work pretty hard going uphill. With RT's temp gauge mod, you really notice . Of course those with OBDII can monitor with a scan gauge and not have to mod the gauge to get more accurate info on engine temps.

 

[98 SNAKE EATER]

I don't believe you have many, if any, long grades in Florida. Even towing you may not notice much difference on relatively flat ground. It's when the 1FZ has to struggle to maintain speed that you notice the engine temp climb, at least in my experience. And as most of us know, our engines work pretty hard going uphill.

True, it's relatively flat, but on my trips to Tallahassee I'm constantly downshifting on I-75

Lots of grades that kills my speed from 80mph to 60mph in seconds and seems to take forever to get back up to speed with the throttle mashed

With RT's temp gauge mod, you really notice . Of course those with OBDII can monitor with a scan gauge and not have to mod the gauge to get more accurate info on engine temps.

Bluetooth and Droidscan Pro FTW

Still no temp issues though

 

[Schwaz80]

Ok. I have the blue hub. Where do I get this 20k fluid?