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Discussion Starter · #1 ·
Trying to source 91.5 to 93 Ram Cummins Intercooled fan hub # 3921688 & pulley # 3917674 but not getting results on goggle search anyone know if there are any cross reference numbers to these parts and where I would likely be able to obtain them?
 

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Do you have the ESN for the engine?
If so go into Quickserve and look up the parts, if the part number is written in Blue not Black click on the number and it will show any superceded part numbers in order from oldest to the latest.
May help in Google searching
Cheers Steve
 

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Discussion Starter · #3 ·
No ESN

Do you have the ESN for the engine?
I have no ESN for those years, the parts are for a conversion of a 2nd gen 12 valve fan hub bracket to the shorter 1st gen w/intercooler optioned 12 valve fan hub bracket & pulley.
 

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The part numbers you have are correct. The problem is that is a very scarce part. I know because I have one sitting on the dresser in the spare bedroom. Took years to find that one. They do show up occasionally on ebay. Not cheap either. The last one I saw sold for $340 last May. Mine still has part of a fan still attached which I need to remove and clean it up when it gets warmer. Might check and see if Dodge has part numbers. Can't imagine what one might cost from the parts counter. Might luck up and they might have one in the obsolete area.
 

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That 91.5-93 fan hub is made of "unobtanium". In know guy who bought an entire 12v 6BT just to get that hub, since its the only "low mount" fan hub that centers the fan with the engine. I would just use one of the later Dodge offset fan hubs - you wont even see the fan once mounted in your custom fabricated shroud. The irony is, that particular hub is supposedly more prone to bearing failure.
 

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Discussion Starter · #6 ·
Just missed a few on the bay

The part numbers you have are correct. The problem is that is a very scarce part. I know because I have one sitting on the dresser in the spare bedroom. Took years to find that one. They do show up occasionally on ebay. Not cheap either. The last one I saw sold for $340 last May. Mine still has part of a fan still attached which I need to remove and clean it up when it gets warmer. Might check and see if Dodge has part numbers. Can't imagine what one might cost from the parts counter. Might luck up and they might have one in the obsolete area.
It appears they demand a premium, I'm just trying to get more space between the fan and the radiator while using a thicker radiator core.
 

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Discussion Starter · #7 ·

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Discussion Starter · #8 · (Edited)
Missed out on good deal for one on the bay & looking for another rare part.

It figures I missed out on three (3) fan hub brackets with pulleys that were available for $225. ea. I suspect they will resurface at higher prices......

Another part I'm looking for is the short power steering pump bracket and gear so I can delete the vacuum pump, if I can't find one at a reasonable price I'll just remove the pump paddles so the vac pump will never pressurize the crankcase if it develops a leak.
 

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The 91.5-93 hub is more prone to bearing failure?

That 91.5-93 fan hub is made of "unobtanium". In know guy who bought an entire 12v 6BT just to get that hub, since its the only "low mount" fan hub that centers the fan with the engine. I would just use one of the later Dodge offset fan hubs - you wont even see the fan once mounted in your custom fabricated shroud. The irony is, that particular hub is supposedly more prone to bearing failure.
 

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Maybe of some use but 4 bolt flange. Sits back fairly well and available.

3285947

Engine Auto part Vehicle Motor vehicle Automotive engine part
Engine Vehicle Auto part Car Automotive engine part
Cheers Steve
 

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Ofelas, the 91.5-93 hub uses the same bearing as the others. No known issues there. Its main problem is it is just scarce in the used market. A fan hub is an item seldom replaced. You just install a new bearing if needed and keep using the old frame.
 

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Gotcha char.

I do have a few new bearings handy, packed in Cummins boxes & plastered over with a Mopar label. Incremental price increases with every layer of labeling :-D

Certainly a better option that uncorking the couple NOS hub/pulley assemblies I stored & forgot about.

Any preference between NSK & Fafnir bearings? I have both.
 

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Seems like the NSK was pretty common. Don't know of any advantage of one over the other. I did a hub a few years back and seems like it was an NSK even though it came in a Cummins box.
 

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Discussion Starter · #14 ·
In the end I had used a 1st Gen pulley a 2nd Gen hub 3rd Gen hub bracket & new bearing the fan remains in the same as it would be for 2nd Gen however; set back for more clearance between fan blade and radiator core. Auto part Vehicle Engine Car Fuel line
 

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Discussion Starter · #16 ·
Having no luck finding parts. A diesel shop said his customers are doing a direct replacement with the 94 pulley, possibly using a different belt depending on ac on/off...would this make the belt sit back too far?
NO; But the fan will be very close to the radiator in some applications. A machinist can cut the center out of 2nd gen pulley out and fabricate to 1st gen turbo configuration.

A 3rd gen pulley center can be cut out then welded the groved outside pulley from the 2nd gen to the 3rd gen....
 

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The '94 up pulley has the same bolt pattern as the '91.5-93 but the belt will not align. Below is a photo showing the 2 pulleys side by side. That IC pulley/hub arrangement can be found occasionally but they are pretty rare and expensive. There's a used set on ebay for $450. If you knew the Dodge part # for the pulley you might accidentally find a dealer that still had one on the shelf. It was a part that was rarely replaced.
 

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Discussion Starter · #18 ·
The '94 up pulley has the same bolt pattern as the '91.5-93 but the belt will not align. Below is a photo showing the 2 pulleys side by side. That IC pulley/hub arrangement can be found occasionally but they are pretty rare and expensive. There's a used set on ebay for $450. If you knew the Dodge part # for the pulley you might accidentally find a dealer that still had one on the shelf. It was a part that was rarely replaced.
What people have resorted to is to cut out the 2nd gen center removing excessive material fabricating a plate to fill the gap because the face of the 2nd gen pulley will be smaller after material is removed and re-welding the plate center to the pulley too the 1st gen specs....
 

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I suppose that can be done. Just have to be sure the pulley is smaller in diameter than the 3rd gen model because it will not clear the 1st and 2nd gen gear housing or you'll need a 3/8" spacer behind the hub assembly. The common rail gear housings were different.
 
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