# front hub bearing ?



## ticki2 (Jan 10, 2006)

A few months back replaced a front hub bearing on the '02 3500. Bought it at the local parts house . They listed the same PN for 2500HD and 3500 DRW . Thought I'd plan ahead and did some shopping online. Came up with a good price on a timken but it shows a different PN for 2500HD and 3500 DRW. Ordered the one for 3500 and compared the old and new , they are slightly different. Looking at the side that slides toward the spindle the new one has rounded lip where it would butt the spindle seat , the old one is slightly indented. Not sure if it's just a design change or the wrong part . The timken # on the box is correct for the listing . Input would be appreciated , thanks


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## ticki2 (Jan 10, 2006)

Here are some pictures


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## B&B (Nov 4, 2006)

As long as you ordered it for a DRW truck it should be correct. The difference is simply a slight design change/difference as you suspect.

And just a FYI: SRW and DRW front hub units ARE NOT THE SAME.


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## ticki2 (Jan 10, 2006)

B&B;549853 said:


> As long as you ordered it for a DRW truck it should be correct. The difference is simply a slight design change/difference as you suspect.
> 
> And just a FYI: SRW and DRW front hub units ARE NOT THE SAME.


I found that out today , half the parts houses only list one PN for both applications. According to the Timken spec sheet I downloaded here is the difference. 2500HD # SP580303--flange dia =8.19 and flange offset = 2.68 . 3500 DRW # SP58309--flange dia = 7.85 and the flange offset = 2.29.

Now the thing is the one that I already replaced came from one of those that only had one listing so I'm thinking it's for a 2500HD. The other point of interest is that the one for the 3500 is always cheaper than the 2500HD , and both seem to fit.


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## B&B (Nov 4, 2006)

They both do seem to fit but only one is correct. If you see in your specs the offsets are different, which moves the rotor in relation to the caliper bracket/brakes. What happen's is the additional offset cause's the caliper to move to far inboard as the pads wear, which will allow the piston to extend too far out of the caliper bore, usually causing a leak.

I have ran into this situation more than once when the incorrect hub is used.


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## ticki2 (Jan 10, 2006)

B&B , you wouldn't believe how many blank stares I got today when I brought the subject up , nice to know there's someone out there that realizes there is a difference.

So it looks like I need to pull the one I replaced off again and checkit for dimensions . 

Do you think the same problem would exist with the brakes using the 3500 bearing on the 2500HD ? Two reasons I ask , one the 3500 is cheaper than a 2500 and I have both and it would be nice to have a spare that fit both.


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## Yaz (Apr 13, 2005)

B&B I bet that's not what he wanted to hear but It's not unusual for a Discount auto parts to mess up.

If it were I, I would be pulling the other hub to see if you got the 3500 hub one last time. If they take the cores you have a small shot you have the right one.


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## Yaz (Apr 13, 2005)

ticki2- you in southern NH?


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## B&B (Nov 4, 2006)

ticki2;549925 said:


> B&B , you wouldn't believe how many blank stares I got today when I brought the subject up , nice to know there's someone out there that realizes there is a difference.


 To many book/computer readers out there that don't know how, or dont care to use a micrometer. All they know is to spit the book/screen at ya.



ticki2;549925 said:


> So it looks like I need to pull the one I replaced off again and check it for dimensions.


 If your not positive which one it is, yes I would check it. Hopefully you got the correct one at the time.



ticki2;549925 said:


> Do you think the same problem would exist with the brakes using the 3500 bearing on the 2500HD ? Two reasons I ask , one the 3500 is cheaper than a 2500 and I have both and it would be nice to have a spare that fit both.


 IIRC, when you go the other way the rotor will rub on the caliper bracket.


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## ticki2 (Jan 10, 2006)

Sometimes ignorance is bliss , now I have 2 projects instead of one. I'll let you all know what I find , all is working good so maybe I'll be lucky---NOT

Yaz , I'm in central NH , next to Waterville Valley

PS These were not discount houses , Napa and Sanels


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## Yaz (Apr 13, 2005)

Too bad because I'm way south, on the border actually. I was just wondering to offer up a hand in your project.

Good luck, hope it goes smooth.


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## ticki2 (Jan 10, 2006)

Yaz , appreciate the thought , it would be kind of a long commute , 90+ miles. I may be able to get the measurements with just the wheel off , we'll see . Have to wait some , wintery mix coming tomrrow , don't you love that term , means they haven't got a clue . We still have 2 or 3 ft . you must be down to bare ground .


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## Yaz (Apr 13, 2005)

It's all gone after yesterdays rain.. Some in piles, but my grass is bare.


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## ticki2 (Jan 10, 2006)

OK , tackled the front wheel bearing again this morning and here's what I found. The one I put on ( SKF BR930416) is the same dimensions as the one that came off and the new one which is a Timken SP580309 , all for the 1 ton DRW. The SKF BR930416 from Napa and Sanels is listed for 2500 HD and 3500 DRW and SRW , same part number. Timken has 2 listings , SP580309 for 1 ton DRW and SP580304 for 2500HD . GM has AC Delco FW287 for 1 ton DRW and FW 289 for 2500HD. Sanels was $100 cheaper than Napa , same part and manuf. The new Timken I purchaced online was a $100 cheaper than Sanels . All three that I've delt with have Timken bearings in the hub , go figure

The difference according to Timken

1 ton flange dia = 7.85 " flange offset = 2.29"
3/4 ton flange dia = 8.19" flange offset = 2.68"

Can anyone verify the dimensions for the 2500HD from an old one they have taken off or a new one they are putting on.


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## ticki2 (Jan 10, 2006)

Surely someone has an old 2500HD hub bearing laying around they could measure up .


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