Just bought a 2002 1500 quad cab 4x4 4.7L NV3500 manual 5spd with 159,000 miles on it and going to replace all transmission fluids.

Does anybody see an issue with using Amsoil for the following applications:

1. Rear Diff LSD 9/25 - Amsoil Severe Gear 75W90 Synthetic EP
2. Rear Diff LSD 9/25 - Amsoil Slip Lock Differential Additive (friction modifier)
3. Front Diff - Amsoil Severe Gear 75W90 Synthetic EP
4. Manual Trans NV3500 - Amsoil Synthetic Manual Synchromesh Fluid 5W30 (replacement for Chrysler 4874464)
5. Manual Transfer Case - Amsoil Synthetic Automatic Trans Fluid

I know the Owner's manual says the transmission fluid never needs to be changed - but c'mon - 159,000 miles? I wouldn't be able to sleep at night.

Has anybody had a negative experience with Amsoil products?

Any help would be appreciated.

Blake

 

Amsoil is good stuff. Regarding the NV3500, as long as it says it's a replacement for the Chrysler fluid, use it. I personally use Pennzoil synchromech in mine. I also add an extra quart as I think 2qts of fluid just isn't enough. My tranny has nearly 220k miles on it with nearly 40k of those making much more torque than stock.

FWIW I tried Redline MTL in mine and didn't care for how it shifted.

 

You don't need the modifier with the Synthetic rear fluid. Already has it in there, but you can add it in if you want. Too much isn't good though so I'd try it without first.
You want 75w-140 for the rear as well, 75-90 goes up front, but you need the heavier stuff out back.

READ the Maintenance and Fluid specs thread I have made. https://dodgeforum.com/forum/3rd-gen...nce-specs.html

 

Thanks guys. Hahns - I had thought about the RedLine and Royal Purple. I just couldn't seem to find as much information on RedLine, and I heard that once RP was used, you could not revert back to a non-RP product. Don't know how true that is.

DD - I better check my source on the rear before I start pouring stuff in there. I had heard that you still might hear chatter without the friction modifier, and if you do, just put the small 4oz bottle in. Can you describe what problem it creates if too much is in there? What does too much friction modifier do?

As far as I know, everything on the transmission is ok except a slight whining in the rear diff when you let off on the gas. I don't think its a carrier bearing because I think that would whine whenever the wheels are turning. I think that only leaves the pinion bearing? I'm hoping when the new fluid is in that the sound is reduced.

Also, what size is the allen nut for the drain plugs? It looks huge!

 

It is 17mm.

IMO/experience, at 159k, the there's probably not much left of the LSD, so it's highly unlikely to chatter, especially when using an oil designed for LSD use. FM reduces friction which helps prevent LSD's from chattering, but also makes the LSD less effective.

 

Are you sure about that?

I know Royal Purple doesn't need the additive but my Amsoil rep has told me personally to use it with all my trucks with stock limited slips in the rear.

I will say that I havent changed the fluids in this one yet so I dont know what he will say, but like stated he has always told me to use it for my other ones and for all those the fluid wasn't made with the intention of not using the friction modifier in those setups.

 

I've heard both ways - that the SeverGear already has it in there, and that you should put the friction modifier in there regardless.

I'm still trying to understand two things:
1. If I don't put the friction modifier in, and I hear chatter like during turns, am I damaging my differential? Or, just allowing for an irritating sound?

2. What happens if you have too much friction modifier? Hans said it makes the LSD less affective - like maybe power will not shift to the wheel needing it.

I think when I put this stuff in, I will not include the FM, wait and see if there is any chatter on my diff with 159K miles on it, and IF I get the chatter then just put it in.

That is of course if somebody confirms that this approach does not risk damaging the diff.

 

I have Mobil 1 LT 75w-140 in the rear differential with NO additional Modifier added.
I've towed very heavy loads and have done very sharp turns with those loads. Never, not one time did my rear end chatter.

To much friction modifier will burn up your clutch pack. It provides much more friction than needed and just like with no modifier, too much modifier will create chatter in unnecessary situations. Modifier isn't all that great for seals either(dries them out) yes, there are additives in the oil that do help prevent that.

You can drive for a little while with the rear end chattering before you'll burn it up so dont be too concerned about a drive back-forth to work with it chattering if you didn't add any modifier in.
I'd say on a perfectly good clutch pack, it would take 6-8mo of chatter not towing anything before you fully burn up the clutch pack, so it's not as quick as you think.