Dorman Diff cover for 10.25" rear. O-Ring or Gasket?

[WrenchWhore]

Hey guys! I'm overhauling a 10.25" rearend and found this guy on Amazon used(same cover as Dorman PN 697-725 but from Yukon. PN: YP C5-F10.5)
. Figured it would be nice addition for when I start towing in the AZ heat. Also, my current cover is bent and leaking. All the searching i've done shows no O-ring to seal it but it's got the grove cut into the sealing surface just like Mag-Hytec and Banks. As a backup I got a Lubelocker gasket for easy draining/inspections/gear oil changes if the O-ring deal doesn't work out. Any input on what's going on here? The groove itself looks like it was cast in then they machined the surface flat. Seems like it would leak being porous and not smooth like the machined sealing surface is. Maybe they abandoned this idea during production???

 

[Rdnck84_03]

My guess is that it likely had a product specific gasket originally. Since most people don't use gaskets on the diff cover anyway, they were probably discontinued due to limited sales.

James

 

[XOLATEM]

My guess is that the groove is for the RTV sealer to make its own o-ring.

I saw that method a lot from working on k****a equipment.

I was not impressed...mainly for the reason that I had to seal something up and then wait a day to put oil in it...'they' made me use the 'factory-approved sealer' instead of something good like Right Stuff...

Anyway...that looks like a nice cover...if you run your truck and then shoot the cover with a thermal gun to get a baseline...then put on the new cover and run it and test...you will see if it runs any cooler...

Just a thought.

 

[trackspeeder]

The original cover was a one year deal found on the V 10 SuperDuty.
You will need longer bolts. Fill the groove with RTV. If you want to keep the clean aluminum look. Give it a couple coats of clear finish.

 

[WrenchWhore]

The original cover was a one year deal found on the V 10 SuperDuty.
You will need longer bolts. Fill the groove with RTV. If you want to keep the clean aluminum look. Give it a couple coats of clear finish.

I was hoping to use my Lukelocker gasket but it that doesn't seal theres always RTV. I did source longer bolts before as well. Heard a lot of people upset about it not having longer bolts.

 

[WrenchWhore]

Anyway...that looks like a nice cover...if you run your truck and then shoot the cover with a thermal gun to get a baseline...then put on the new cover and run it and test...you will see if it runs any cooler...

Just based on all the research Banks did on diff covers I think this will be a great upgrade. Nothing close to there ram air design but better than flat back diff covers. I do have a laser thermometer so I will give it a shot. Once I get all my trailer wiring and receiver sorted out i'd like to do some research. I've also heard of those Temp stickers you stick on things that get hot. I've see them on racing shocks but a diff cover seems like a good application as well.

 

[Cubey]

My guess is that it likely had a product specific gasket originally. Since most people don't use gaskets on the diff cover anyway, they were probably discontinued due to limited sales.

James

I have previously used this brand of reusable gasket without RTV on a dually D70 and it worked well, with repeated use. The oil was nasty in the RV so I changed the oil several times in just a few years to clean up the gears and bearings, so it saved money on RTV/gaskets and time/mess.

The Sterling version: https://www.riffraffdiesel.com/lubelocker-ford-sterling-10-25-10-5-differential-cover-gasket/

 

[WrenchWhore]

I have previously used this brand of reusable gasket without RTV on a dually D70 and it worked well, with repeated use. The oil was nasty in the RV so I changed the oil several times in just a few years to clean up the gears and bearings, so it saved money on RTV/gaskets and time/mess.

The Sterling version: https://www.riffraffdiesel.com/lubelocker-ford-sterling-10-25-10-5-differential-cover-gasket/

That is the exact gasket I ordered as a backup. I'm a huge fan of LubeLocker since I do all the servicing myself. It's just downright a better gasket in all areas. Saves easily an hour of cleaning off old silicone, applying new and letting it set up.