Aftermarket Diff. Covers and Fluid Which 1?

[guyhaz]

Just bought a 03 3500 DRW w/ 200k miles on it. I have been slowly doing maintenance on it and I am getting ready to change the diff. fluids. It has an 11. 5 rear end 3. 73 gears. Looking at putting an aftermarket cover while I am changing the fluids. Which covers are the best and what size do I buy? Also what is a good fluid to put in? I pull a large heavy horse trailer and a quad trailer with this truck.

 

[Jim W]

Several members like myself use the Mag-Hytec covers for our trucks. Some use the covers on the front and rear and some just on the rear diff. Contact Geno's garage for the correct size for your truck.



I use Amsoil server duty diff oil 75W-90 others use 75W-140 oil. Amsoil offers three different grades of oil, for your driving style and needs. I use this site for all of my fluid needs. Click on the recommend material and read the definition on the material and recommend use, for your needs.



AMSOIL Online Product Application Guide



Jim

 

[marcus weeks]

afe just released one for the rear. its like mag-hytecs but its finned on the inside as well. nice peice, but like all, not cheap.

 

[Spooled05]

Mag-hytec rear w royal purple front and rear!

 

[MMeier]

X3 on the Mag Hytec's , I've been using LE (Lubrication Engineers) 607 , now 1605, IIRC for lube. No problems with 233k on my '03, most of it hauling something heavy. Just was down at Firebird this past weekend with the race car .

 

[guyhaz]

Leaning towards the Mag-Hytec with royal purple 75/140... anyone have any thoughts on the PML diff cover?

Thanks to everyone for their replies... gotta luv this site and all the help!

 

[Bob4x4]

The PML is cheaper but does not match the quality or oil quantity of the mag cover,The new AFE cover looks awesome and is die cast so it will be VERY easy to clean. The fins on the inside (running in the oil)have to help in heat transfer They also have more fin area on the outside from what I saw wich should equate to better heat transfer.

 

[EBolgiano]

I've had the PML rear end and transmission pan on my 2005 for 5 years with no problems. Been real happy with them. Ed B

 

[rbattelle]

There has been speculation in the past (admittedly no documented proof) that the closer fit between the ring gear and the stock differential cover was intentional, in order to help carry oil to the top of the ring gear.

With that logic, the PML cover is more desireable than Mag-Hytec because clearance with the ring gear is smaller on the PML.

I'm not saying I accept this, but I thought I'd point it out. Frankly, I think either the PML or Mag-Hytec is a good choice.

I'm still living in the stone age - running the stock cover.

-Ryan

 

[CamarosRus]

Recently changed my 2WD diff to REDLINE 75-90 (4qts) on my 87K mile 2003.



I cleaned and reused factory gasket. Torqued bolts to 30 ft#. Also used LOCTITE Blue on threads.



Used cheap Harbor Freight (saw same in Snap On catalog) hand pump to xfer fluid from bottles to fill hole.



I removed spare tire, so as to easily remove diff cover. I then media blasted and painted cover (They are unpainted new) with RUSTOLEUM primer and 7777 Satin Black.



Also used FLUID FILM Rust Inhibitor on cast iron center section after removing flacky rust.

 

[AH64ID]

I have a MH rear and use Amsoil. The front is stock for now, but will be getting a PML at my next fluid change. I like the MH on the rear, but don't need the added cooling up front, the PML has a drain port and will do everything I need.

 

[MMeier]

Just curious, why is the added cooling not needed up front ?

 

[AH64ID]

The front doesn't have continuous power applied to it, even when in 4wd the load isn't as great due to decreased traction conditions, and when the traction is decreased its often in winter and cold out anyhow.