1994 K3500 extended cab dually

[dbrannon79]

I wonder if you can find any numbers on the old seal or perhaps get the housing OD and shaft size for the seal ID and just find one by size. Napa usually can find one by the size in their paper catalogs.

 

[n8in8or]

Thanks so much for sharing the details. How did you remove the tone ring for the output shaft? Regular two or 3 jaw puller? I remember there was a fellow on here a couple years ago struggling to rebuild the same unit and he couldn't seem to be able to remove the ring or read that to disassemble the manual said to split/ essentially destroy the part.

Did you re- use the clutch coil or were you able to find a replacement? That also seems to be an elusive part and I'd love to know where to get one if you found a legitimate source

Yeah, I just used a 2-jaw puller to remove it. It came off pretty easily. There's another version of the tone ring that has a smooth bore instead of the splined one like mine - I imagine that one is tougher to remove. The smooth bore tone ring is a little more readily available, but unfortunately it doesn't appear to be backward compatible.

I just re-used the clutch coil. From what I've ready, the synchronizer doesn't seem to be a part that keeps the transfer case from functioning....it's just some added feature they added for some reason. I didn't fiddle with it too much while assembling to try to understand it, but the little I did, I believe it would engage the front output using the friction of the steel discs applied to each other until they slipped enough for the splines to engage. I guess they thought that would be something that someone with a K3500 would want? It doesn't make a ton of sense to me.

 

[n8in8or]

I wonder if you can find any numbers on the old seal or perhaps get the housing OD and shaft size for the seal ID and just find one by size. Napa usually can find one by the size in their paper catalogs.

I was able to find a number on the old seal, but it didn't help me with cross-referencing. I'm not sure the goons at the local Napa would be very helpful in trying to cross-refence this seal - it used to be Napa was where you went for better parts and service around here, but it seems they've dumbed themselves down with the same shlocks that work in the other places.

I did do some creative cataloging later last night to see if I might find the seal, and I think I did. The BW1356 appears to use the same shift shaft seal as the BW4401, and was a much more popular transfer case, as that was used in OBS F150 through F350s. When I was looking for the seal, I was looking up a 1994 F150 to see if I could find the seal, but I was coming up with the same seal I already had (which turns out was for the electrically-shifted case, not the manual one). But then last night I got curious and decided to look at the 1997 transition year when the F150 was the newer style, but the F350 was still the OBS. There was one seal that came up in the RockAuto catalog, and it appears to be the right one:

More Information for WJB / INMOTION PARTS WS710690

That number, 710690, is different than what's on the original seal I have, but that does come up with some readily available seals from various manufacturers including Timken. I didn't go out and measure the bore and shaft in the case, but the sizes listed in the catalog do seem reasonable for the application.....the seal I received was much smaller. At this point, I might as well just wait for the seal kit to show up, since that was only $17, so the single seal won't really save me any money, and the truck isn't ready for the case to be installed anyway, but if the seal kit doesn't have what I need, then I can explore that other seal further.

 

[n8in8or]

I received the seal kit yesterday.



Here are the 3 shift shaft seals I have now. Left to right are: New from kit, New all the catalogs call for (actually for electric shift) and then the new one from the kit. It’s a match.



Here’s a close-up of the original seal:



Here’s a close-up of the correct replacement seal:



I tried looking up the number on the correct seal and I still can’t find anything. The input and output seals have no info on them, so I guess I’m still happy I paid extra for the Timken seals originally.

 

[n8in8or]

Oh, and it’s been 2 weeks since I ordered the speedometer tone ring from Jegs and I haven’t heard anything yet, so I’ll have to call them this week. I’m guessing I’ll just be putting the original one on with Loctite.

 

[Will L.]

Hopefully it Wasn’t shipping out of the Ca location

 

[n8in8or]

Hopefully it Wasn’t shipping out of the Ca location

My gut feeling is their catalog isn’t correct and they can’t actually get the tone ring. The part I don’t get is why the order hasn’t been automatically cancelled though. Not a big deal, it’s just curious.