LBZ Fan Clutch

[johnmyster]

Summer is coming, fifth wheel is checked over, lots of campground reservations made.

When it's hot out, on extended grades I will see 220-225 (digital gauge) before fan clutch engagement. Aside from grade efforts, towing stays under 200. Cooling stack is clean. My truck has had the wagon wheel (inner shroud) removed by prior owner, likely during water pump replacement. I'd like to get fan engagement a little earlier to help keep coolant and oil temperatures down during grade pulls. (L5P oil cooler is on the upgrade list.)

I see that Merchant and Kennedy offer a "lower temperature" LBZ/LMM clutch. Is there any reason to believe it is any different than the Hayden 2886? Is there a Borg Warner (?) OE equivalent that I should track down instead?

Edit, appears the OE kodiak part might have been a Behr. I'm also seeing part numbers 15816068 (LB7?), 15205968 (LB7?), and 15083219.

 

[Ron Nielson]

As long as you aren't overheating i.e the fan clutch really locks up (you'll hear the big fan roar) and starts the temp down, or at least it holds the temp from going up more, I wouldn't try to improve with a fan clutch. Back off the throttle a little, Maybe even drop the trans a gear. Boiling point is something near 260 with a 15 lb cap and 50/50 mix

 

[N2BRK]

Kennedy and his fan clutch are crap. Sent me one right before my trip and it was bad. I had to buy one at the dealer to make the trip and he refused to refund me. Lots of threads similar to mine - bad clutch and A/C will not work because it overheats. He's the only asshole I've every dealt with that will send you something DOA and refuse to refund. Many people have had the same problem with his fan clutches - google is your friend. Dealing with him on the phone was like talking to a brick wall - he's an asshole.

 

[jlawles2]

I ran the 2886 on one of my trucks. Good fan, temps stayed in check.

I believe Adam (malibu) ran the 2886 on his hot shot rig for a long time before going spool in the summer. He had good results, but when he was having summer heating temps and the fan clutch would not come on fast enough he swapped to the spool to get ahead of the heating issue.

 

[johnmyster]

I ran the 2886 on one of my trucks. Good fan, temps stayed in check.

I believe Adam (malibu) ran the 2886 on his hot shot rig for a long time before going spool in the summer. He had good results, but when he was having summer heating temps and the fan clutch would not come on fast enough he swapped to the spool to get ahead of the heating issue.

Was your feel that the 2886 responded faster than the stock and/or prior clutch you had? Did you feel it was excessive?

Al this assumes that my OE clutch with 300k miles on it is properly functional (seems to be similar to other internet accounts) and that yours was as well. It seems like an easy $100 to buy some overall towing margin with little impact on non-towing behavior.

I'm not afraid of 225 occasional coolant temps per-say, but I have a feeling oil temperatures are pretty toasty by the time we get there, as evidenced by oil pressure beginning to fall.

 

[jlawles2]

The 2886 reached full lock a bit sooner than the stock fan and was I believe a bit stronger locking.

One of the biggest issues is cooling stack plugging. You would be amazed at how much crap gets stuck between the stacks that you think you washed out. It's a bit of a pain, but pull the top of the core support off, then pull the radiator and the intercooler (CAC) and clean them.

I still have a Banks cooler for a LBZ that I pulled when I traded it in. This is how I know there gets to be a lot of stuff between them.

 

[Dozerboy]

You need to get a inner shroud installed. Their have been plenty of discussions about trucks struggling to keep cool without them.

Definitely seems like your clutch is weak. Mine locks up around 215* IIRC.

 

[johnmyster]

You need to get a inner shroud installed. Their have been plenty of discussions about trucks struggling to keep cool without them.

Definitely seems like your clutch is weak. Mine locks up around 215* IIRC.

If this is the case, do I...

1) $185 delivered on a new inner shroud.
2) $80 on the Hayden lower temp clutch, which moves the fan closer to the core (into the outer shroud) which may help the lack of inner shroud.
3) 1 and 2
4) Slow down a little on hills.

 

[2004LB7]

If this is the case, do I...

1) $185 delivered on a new inner shroud.
2) $80 on the Hayden lower temp clutch, which moves the fan closer to the core (into the outer shroud) which may help the lack of inner shroud.
3) 1 and 2
4) Slow down a little on hills.

1 & 4

And possibly 5 for a new fan clutch if yours is bad. But start at a known data point. With your shroud missing there is no way to know if it is your shroud or clutch causing the issue. So put everything to stock and see if you still have problems. Then go from there

 

[PureHybrid]

I vote new clutch and shroud

 

[jlawles2]

What part of the shroud is missing? It sounds by your first post that the section behind the fan (LBZ encapsulated the fan in the shroud) making it almost impossible to change the belt was removed. Post pictures as this will help determine which portion is missing.

I did remove the section between the fan and the belt on mine, but I did not tow heavy with mine. The upper and lower portions were in tact and tight to the fan as they should have been, just that inner section was removed.

 

[Ron Nielson]

1) $185 delivered on a new inner shroud

Sounds like a junkyard part is in order

 

[johnmyster]

What part of the shroud is missing?

Upper and lower shrouds are there. I was referring to the "wagon wheel" inner/rear shroud that is commonly removed the first time a mechanic has to pull the fan. I imagine mine was taken off when prior owner had water pump replaced.

1) $185 delivered on a new inner shroud

Sounds like a junkyard part is in order

The pull-a-part yards near me only rarely have diesel/hd trucks. It's usually a waste of time for me to visit them but I do have a few things on my list. I can only imagine that the inner shroud would get taken out with the motor pull and potentially cut apart if someone was trying to get at something.

 

[johnmyster]

I vote new clutch and shroud

What is your take on replacement clutches? Hayden is fine or get spendy with OE? Kodiak (lower temp) or stick with factory fitment?

If I really wanted to do the job twice I could put on a shroud then see how it responds as warmer weather approaches...then do the job again with a new clutch.

EDIT - We took a trip in hills this weekend. Temps were largely well managed when cruising, stable at 195 and under. I saw 205 once on a grade effort in 3rd gear. That said, ambient was friendly at ~70 to 80 F on the trip up and ~55 on the return trip.

 

[PureHybrid]

I put a Hayden on mine, it was listed as "HD" I know that much. I'd have to dig and find the number, it's been years. Mine never got hot, but changing out the clutch did help the A/C in slow traffic.

A side note, look the clutch over really good if you buy new, and the box as well. The first one I received had the box wet, like the fluid inside leaked or whatever. Returned it promptly

 

[johnmyster]

I put a Hayden on mine, it was listed as "HD" I know that much.

The factory equivalent Hayden for my truck (and I believe an 04) is the 2850. The kodiak for the same year is the 2886. Hayden lists them both as "Severe Duty" models.

 

[PureHybrid]

I checked on my previous order, was a Hayden 2843 which is listed as the severe duty on RockAuto for my app

 

[johnmyster]

Weird. Some listings show a 2850 for a LBZ. Others show it specific to the LMM and have the 2843 for an LBZ.

So my quandry still remains.

Reading the forums it's tough to discern if guys are judging engagement temperature by the dash gauge or by a digital readout. It's also tough to tell if they noticed an improvement because they had an old/bad/marginally good clutch and replaced it with a new one, or if the 2886 is actually lower engagement than the factory equivalent.

 

[PureHybrid]

Mine was getting weak for sure. I can't say that the fan comes on sooner, but it is stronger. If I leave the winter cover on when it's warm the clutch will start engaging fairly easy, well before the lie-o-meter on the dash says it's 210

 

[darkness]

I’ve had the 2886 on 3 trucks for sure. Don’t remember if I put one on my first truck. I never towed with my Lbz to know how it worked but it worked. In my ‘02, it engages at 194 like clockwork…when I’m not towing. It engages quite a bit higher when I am towing. But the truck runs cooler than it did before the change. On my Kodiak, it seems to run backwards. Super noisy while driving around town with or without a trailer. But can’t hear it hardly at all when the truck starts warming up. I reserve judgement though till I get other things straightened out. I do have a solid hub ready to go when I’m ready to blow up my fan blade.