Dodge Challenger Forum banner
  • Hey everyone! Enter your ride HERE to be a part of September's Ride of the Month Challenge!
1 - 20 of 21 Posts

·
Registered
2021 Challenger 392
Joined
·
8 Posts
Discussion Starter · #1 ·
I’m planning to swap out the factory rear differential fluid on my 2021 scat pack 6 speed.. do I need a rear differential cover gasket? The folks at summit couldn’t find the part and suspect it might be silicone..
 

·
Super Moderator
Joined
·
17,235 Posts
no - there's a fill plug and drain plug (they have integral gaskets on them)

the factory fill is a synthetic GL-5 lubricant. No need to change what you have.

in the future, you'll need to make sure there's friction modifier in the fluid for the limited slip clutch packs.
 
  • Like
Reactions: 19johned53

·
Registered
2021 Challenger 392
Joined
·
8 Posts
Discussion Starter · #3 ·
no - there's a fill plug and drain plug (they have integral gaskets on them)

the factory fill is a synthetic GL-5 lubricant. No need to change what you have.

in the future, you'll need to make sure there's friction modifier in the fluid for the limited slip clutch packs.
I have trust issues... It would help me sleep better if I could open up the differential, clean and swap out the fluid..
 

·
Registered
Furious Fuchsia 2010 Challenger R/T Classic A5
Joined
·
598 Posts
I'm not certain about the '15+ ZF diff, but the prior Getrags & non-Getrags have a fill plug up high on the diff and a drain plug down low. Remove the fill plug before the drain plug so you don't air lock it! The plugs are tapered pipe thread so a few wraps of teflon tape is all you need to reinstall.

Mopar doesn't service pumpkin internals so the service manuals are rather lacking in specs. I scraped red sealant off mine (anaerobic RTV?) so when I put on a new cover I used red Loctite 518 Gasket Maker. It's been over 5 years now and never a leak.
 
  • Like
Reactions: bigraf

·
Banned
2021 Scat Pack
Joined
·
206 Posts
I thought so. If you really want to go full nerd do what I do pump new fluid in to ‘wash’ out the old fluid before you refill.
 

·
Registered
Joined
·
1,082 Posts
There is a youtube video of a guy who has the same sleepless nights issue as you. He runs fresh gear oil through the pumpkin until it runs clean. Note: I know he owns a Charger.

 

·
Registered
2021 Challenger 392
Joined
·
8 Posts
Discussion Starter · #9 ·
There is a youtube video of a guy who has the same sleepless nights issue as you. He runs fresh gear oil through the pumpkin until it runs clean. Note: I know he owns a Charger.

It’s a curse. One question.. why the “pumpkin” alias for the differential? (Yes, I’m a noob)
 

·
Registered
Joined
·
1,082 Posts
It’s a curse. One question.. why the “pumpkin” alias for the differential? (Yes, I’m a noob)
Old school slang. I've been around since the dinosaurs roamed the Earth. There are a few other less commonly known terms for a differential but the old timers (to me) always used, "pumpkin".
 

·
Premium Member
2018 Scat Pack SHAKER in Plum Crazy- GONE :-(
Joined
·
4,703 Posts
It’s a curse. One question.. why the “pumpkin” alias for the differential? (Yes, I’m a noob)
The size and shape of old solid axle differentials. And they used to be more visible.
1022672
 
  • Like
Reactions: bigraf

·
Registered
2016 Challenger R/T Plus Shaker
Joined
·
668 Posts
Pumpkin, hogshead, chunk, third member, just more old school names for it. These ZF differentials are not meant to be serviced, beyond fluid changes as needed. It is a bit involved to remove the pumpkin to remove the cover, so just drain and refill with the correct lubricant as noted.
 

·
Registered
2020 Dodge Challenger Hellraisin Scat Pack
Joined
·
4,185 Posts
I have trust issues... It would help me sleep better if I could open up the differential, clean and swap out the fluid..
You want to sleep better? Think about after you open up the diff and clean it out and then reseal the cover and refill with fluid then something goes wrong how the dealer could very likely deny warranty coverage because the diff was opened up.

If the thing needed cleaning out this is way past due.

Just drain the fluid and then refill with the fresh and with the correct fluid. There can be an additive that needs to be added. You'll have to research this.

I have never done the diff fluid (or tranny fluid) service on my cars since the first car decades ago. The fluid stinks, is messy at Heck. A tranny fluid and diff fluid service at the dealer is a bargain compared to doing this at home.
 

·
Registered
2021 Challenger 392
Joined
·
8 Posts
Discussion Starter · #16 ·
I'm planning on changing mine per the factory service schedule.

Same on my A8.
The reason I even consider this is because of the break-in metal shavings some believe to be an issue.. It makes sense.. but I’m no engineer to dispute the claim and figure that $30 worth of fluid and something to do on a Saturday morning is not worth losing sleep over.. anyways, all good points here. I’ll try and sleep on this and make a decision soon.
 

·
Registered
'16 A8 Scat Pack
Joined
·
10,890 Posts
The reason I even consider this is because of the break-in metal shavings some believe to be an issue.. It makes sense.. but I’m no engineer to dispute the claim and figure that $30 worth of fluid and something to do on a Saturday morning is not worth losing sleep over.. anyways, all good points here. I’ll try and sleep on this and make a decision soon.
I double checked my '16 manual for 392 service intervals.

If not using for Taxi or Towing,

Check Differential Fluid Level every 48k Miles.

Works for me. I'll check it and leave it alone. When and if it starts making noise, the dealer can replace it under warranty.

Their service recommendations, I'll follow it.
 

·
Registered
2021 Challenger 392
Joined
·
8 Posts
Discussion Starter · #18 ·
I double checked my '16 manual for 392 service intervals.

If not using for Taxi or Towing,

Check Differential Fluid Level every 48k Miles.

Works for me. I'll check it and leave it alone. When and if it starts making noise, the dealer can replace it under warranty.

Their service recommendations, I'll follow it.
Thanks for all the input- after discussing with a buddy... risking losing the warranty coverage is not worth it (as also mentioned above by @Rockster above). Thanks again for all the feedback!
 

·
Registered
Joined
·
7 Posts
It’s a curse. One question.. why the “pumpkin” alias for the differential? (Yes, I’m a noob)
Ive always known pumpkin to be same as 3rd member which is removable such as on a ford 9". Not like a chevy 12 bolt where you have a removable cover and ring & pinion load in from the back.
 
1 - 20 of 21 Posts
Top