What fluids to run?

[620mac]

When my first oil change is due, I plan on going Royal Purple in the motor, trans, and rear end. I also want to add LubeGard Platinum in the trans, and LubeGard limited slip supplement in the differential. I have the 8 speed trans, 3.92 gears, and non-slip differential.

What are the factory fluid types and weights?

Will all this work?

 

[SyN]

The ZF 8HP70 Transmission is a Very Complex Transmission! I would only use what fluid ZF recommends!--->Just Me
I would definitely not add any so called additives in this Transmission!

RP every where else I'm sure would not be an issue.
5W-20 or 0W-20 in the 5.7L
75W-140 in the rear end

 

[NYCruiser]

The 8-speed tranny is sealed with no service requirement. It doesn't even have a dipstick.

The factory fill for the hemi is Penzoil conventional oil, 5w-20

The diff's have Mopar Full Synth in them with Mopar friction modifier additive, if required, for the LSD. The weights are all in your owner's manual. The manual is downloadable online if you don't have it handy. Just google it.

 

[14hemiexpress]

I second not changeing fluid in the 8speed. Any full synthetic everywhere else will be find just make sure you get the right friction modifiers for the diffs.

 

[jwheeler]

I would definitely not add any so called additives in this Transmission!

What he said. Everything else sounds good.

 

[jwheeler]

The 8-speed tranny is sealed with no service requirement. It doesn't even have a dipstick.

There is no such thing as a "sealed" transmission. There are many different automatics that don't have a dip stick. There are just different ways of filling them and checking the fluid. No service interval doesn't mean it shouldn't be serviced. When a manufacturer claims a part is "filled for life", that is typically the life of the warranty.

 

[620mac]

So basically from what I'm gathering, leave the transmission alone, run RP 5w-20, and RP 75w-140 in the back? The dealerships can change the transmission fluids on these pretty easily, and it's probably designed so you have to take it in to get it serviced so it creates business for them.

Any thoughts on using the LubeGard with the RP in the rear end? I want to use the best possible fluids with the best possible additives to keep the truck running as good as possible.

 

[DavidRam]

Have you thought of Redline oil and diff fluid? It tends to quiet the engine, and can reduce or eliminate the hemi-tick.

 

[SIhemi]

I switched from amsoil to royal purple and not really happy with rp. I now have the hemi tick that I never had before. I'm going back to amsoil on my next oil change. I also did amsoil in my rear and transmisson.

 

[SyN]

620: "So basically from what I'm gathering, leave the transmission alone, run RP 5w-20, and RP 75w-140 in the back"

Yes! Leave the 8HP70 to your dealer! Just be aware-->The filter is actually built in to the pan. The pan cost is around $300 to replace. The pan is composite not metal. I talked with Joe @ ZF-->He recommended to Me to have the fluid changed around the 60K mile mark. If you tow alot or abuse the heck out of your truck? Do it earlier. Just a small tech tip.

You can add which ever brand of Motor Oil and Gear Lube.

Just use the correct Viscosity!

 

[NYCruiser]

There is no such thing as a "sealed" transmission. There are many different automatics that don't have a dip stick. There are just different ways of filling them and checking the fluid. No service interval doesn't mean it shouldn't be serviced. When a manufacturer claims a part is "filled for life", that is typically the life of the warranty.

Yes, the dealer can check the fluid using "special service equipment" according to the owner's manual:

Fluid Level Check — Eight-Speed Transmission
The fluid level is preset at the factory and does not require
adjustment under normal operating conditions. Routine
fluid level checks are not required, therefore the transmission
has no dipstick. Your authorized dealer can check your
transmission fluid level using special service tools.

The manual also says:

Fluid And Filter Changes — Eight-Speed
Transmission
Under normal operating conditions, the fluid installed at
the factory will provide satisfactory lubrication for the
life of the vehicle.
Routine fluid and filter changes are not required. However
change the fluid and filter if the fluid becomes
contaminated (with water, etc.), or if the transmission is
disassembled for any reason.

I wasn't comfortable with this in a tow vehicle (as opposed to the cars they have put these in for years), so I opted for the 6-speed. Time will tell how these hold up to truck applications.

 

[Jaxyaks]

Yes, the dealer can check the fluid using "special service equipment" according to the owner's manual:

Fluid Level Check — Eight-Speed Transmission
The fluid level is preset at the factory and does not require
adjustment under normal operating conditions. Routine
fluid level checks are not required, therefore the transmission
has no dipstick. Your authorized dealer can check your
transmission fluid level using special service tools.

The manual also says:

Fluid And Filter Changes — Eight-Speed
Transmission
Under normal operating conditions, the fluid installed at
the factory will provide satisfactory lubrication for the
life of the vehicle.
Routine fluid and filter changes are not required. However
change the fluid and filter if the fluid becomes
contaminated (with water, etc.), or if the transmission is
disassembled for any reason.

I wasn't comfortable with this in a tow vehicle (as opposed to the cars they have put these in for years), so I opted for the 6-speed. Time will tell how these hold up to truck applications.

Which year manual did you find this? I would like to show this to my dealer and put it in the file for future reference when they try to hose me on a tranny warranty repair..seems like they try to get me to change all fluids every 2 miles