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Wheel Bearings - Which rotor do I need


Mhfco6

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Front end noise finally got loud enough for me to investigate and found a VERY worn inner wheel bearing. My question is which rotor do I need? I’ve seen several different part choices including some with and without axle code 84. Can anyone help out here? Thanks.
 


adsm08

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It looks like the difference is that axle code 84, which is 3.45 gears.

The other thing I am seeing is 2.2" vs 2.5" rotors, so try measuring and seeing what you come up with.
 

Mhfco6

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It looks like the difference is that axle code 84, which is 3.45 gears.

The other thing I am seeing is 2.2" vs 2.5" rotors, so try measuring and seeing what you come up with.
Looks like 2.5”. You would know better than me.. what do you think? The spindle measure 2.5” if not more but the shaft the bearing rides on is closer to 2”. Where exactly should I be measuring?
http://a64.tinypic.com/25t9lwp.jpg

The front axle tag is extremely hard to read, any other way to find out about the gears?
 
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adsm08

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Centric lists the 2.2" as fitting the D-28, and the 2.5" as fitting the 3.5. IIRC 91 was a split year, so 91 started with the 28, and the 91.5 got the 35.

Also, it says 2.2" vs 2.5" tall. I'm guessing that is from inner pad surface to outer hub tip.
 

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Centric lists the 2.2" as fitting the D-28, and the 2.5" as fitting the 3.5. IIRC 91 was a split year, so 91 started with the 28, and the 91.5 got the 35.

Also, it says 2.2" vs 2.5" tall. I'm guessing that is from inner pad surface to outer hub tip.

Find a parts store that has both in stock, take a rotor off, and go compare.
 

Mhfco6

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Centric lists the 2.2" as fitting the D-28, and the 2.5" as fitting the 3.5. IIRC 91 was a split year, so 91 started with the 28, and the 91.5 got the 35.

Also, it says 2.2" vs 2.5" tall. I'm guessing that is from inner pad surface to outer hub tip.

Find a parts store that has both in stock, take a rotor off, and go compare.
Looks like it’s gunna be a 2.2”. I’ll have to do just that and take mine to a parts store.
http://a64.tinypic.com/2q8mv42.jpg
http://a67.tinypic.com/34fh1r7.jpg
 
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Mhfco6

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Is it possible that I could get the correct rotor height but still get the wrong axle ratio? Centric rotors are specific to the TTB. 2.5” is the Dana 35 and 2.2” is the Dana 28. Is this the deciding factor then and not the ratio?
 

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It's possible that the D-28 only came in a 3.45 for that year. All sorts of odd things happen when production on something is ending and they are trying to burn off excess inventory.
 

tomw

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Given the tag is beyond legibility, you can determine the ratio by turning the input shaft, counting the turns, for one turn of the output. If that is the ratio in question...
It seems trucks get a LOT more cross fitted components over the model year or at the end of the model year. {I hope the clutch and flywheel I bought are correct for that very reason.}
Another example is the idler fitted to the 85 2.3. You won't find them listed except the actual pulley with the bearing installed. The same complete assembly was listed for subsequent model years, and turned out to be the needed part. Remember when you decide to clean up power steering fluid that rustproofed the engine bay to cover alternator and idler bearings to keep the lube intact.
tom
 

Mhfco6

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It's possible that the D-28 only came in a 3.45 for that year. All sorts of odd things happen when production on something is ending and they are trying to burn off excess inventory.
According to my research I have a Dana 35 front axle. The tag is really worn but looks like it says 3.76.
 
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adsm08

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According to my research I have a Dana 35 front axle. The tag is really worn but looks like it says 3.76.
The tag doesn't say 3.76.
 

Mhfco6

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Mhfco6

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So.. parts store trip confirmed my rotors are the 2.5” tall. On a side note is this the correct tool for the bearing nuts? Thanks.

http://a68.tinypic.com/bfqerc.jpg
 

adsm08

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So.. parts store trip confirmed my rotors are the 2.5” tall. On a side note is this the correct tool for the bearing nuts? Thanks.

http://a68.tinypic.com/bfqerc.jpg
That looks like it's for a full float rear end. I don't think it will work for your front bearings. That snout will be in the way.

I think you need PT 648473.
 

Mhfco6

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That looks like it's for a full float rear end. I don't think it will work for your front bearings. That snout will be in the way.

I think you need PT 648473.
Ok thanks. I thought it looked funny.
 

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