Jax I've got 4:10's in mine also, but I'm not sure if I've got a Power Loc or a Trac Loc. I think you've got to remove the diff cover to be able to tell. Mine has been howling for awhile so I'll be getting into her shortly

 

As far as I know, Dodge never put a Trac-Loc in a rear axle behind a CTD. Powr-Loks only. I know that the "Locking Diff" in the rear of the half tons is a trac-loc, but in the D70 & D80 rear ends, the Powr-Lok is the OEM LS.

 

Well that good info, with my luck if they came in one or the other I'd have the Trac-loc, Thanks.

 

Unfortunately that isn't true......for some silly reason, there were factory LS equipped CTD's that came with the Tlok - why, I don't know!?!? There is no guarantee that a 2nd gen CTD had either LS. The only way to be certain is to pull the cover but if you have a high mileage factory LS and it still works great, it is a safe bet that it is a Plok.

 

CTD NUT I've got 120m on mine and she still works great, maybe I got lucky. What part of the rear diff is responsible for the Howling between 20 and 30mph and is this a costly repair?

 

With 120 k, and the LS works great, it is probably a Plok. As for the howling sound, it is most likely pinion bearings if it is coming from the rear diff but usually if the rollers in the bearings are starting to chip and flake (which causes the howling), you will hear the sound at all speeds - it will just get more audible the faster it spins. If the sound is more pronounced under power instead of coasting, it is likely the pinion bearings. Carrier bearings and worn gears can also cause other howling sounds.

 

The howling is much more pronounced while coasting, thanks for the input.

 

Hmm....that is different.....that is a typical trait of worn carrier bearings.

 

I think it would probably be a pinion bearing. In my old 1/2 ton dodge with the 9-1/4 rear end, that thing ate pinion bearings about every 30-40K, just a bad design. And when it happened, the rear end would start howling something awful, especially when coasting. That's when it was at its worse.