Changing Fluids

Hey all!
As the weather is getting better I am looking to get ready for some projects that the cold weather didn't allow me to do.
One project is maintenance. I am at about 35K miles and was thinking of changing my rear diff oil as well as the front.
What interval are others doing this at? Manual said 60K I think but I feel like thats a lot.
What fluid (brand and viscosity) are everyone using?
How do I know if I need to add anything to the fluids (is anti-slip necessary and how do i know if i have it)
Has anyone changed transfer case fluid - How and what was used?
Does the front diff have a drain plug like the rear?
Thanks in advance all, want to get information together and get materials to make this happen.

Is there a fuel filter interval that anyone is aware of or has done?

Read the last couple pages of the syn thread. If your truck is light to medium duty, 75w90 should do the trick. You manual wants 75w140 in the rear, and 75/90 or close (75w85) in the front, for the 1500. If you put an ester oil in the gears and don't do a lot of towing or wheeling, you can go 100k on that. You only add anti slip if you feel shudder when you hit the pedal, I've never heard anyone using redline needing it.

I will change my fuel filter only if my truck stops running because of lack of fuel.

Burla said:

Read the last couple pages of the syn thread. If your truck is light to medium duty, 75w90 should do the trick. You manual wants 75w140 in the rear, and 75/90 or close (75w85) in the front, for the 1500. If you put an ester oil in the gears and don't do a lot of towing or wheeling, you can go 100k on that. You only add anti slip if you feel shudder when you hit the pedal, I've never heard anyone using redline needing it.

I will change my fuel filter only if my truck stops running because of lack of fuel.

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are you saying 100K on what is in there now or once I change the fluid? I will certainly be using redline. Ive stockpiled bottles for oil changes now. What kind of ester oil would be used?

Redline = Ester Oil, yes after you change it you can go 100k is my opinion and what i will do in my truck.

Burla said:

Redline = Ester Oil, yes after you change it you can go 100k is my opinion and what i will do in my truck.

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Always a great source of information! Thank you!!

I'd personally never let my diff oils in for 100k. I don't care how good of am oil is used. I service both diffs, transfer case and transmission every 30k. It's cheap insurance for me, personally.

These trucks cost too much money to skimp on fliud changes. If you want to let it go to 100k, that's your choice.

Just a side note: I always pull the fill plug first before I drain the diff or transfer case, just in case the drain plug comes out fine but then you can't for some reason get the fill plug out. Don't ask about how I figured this out??????
Jay

I respect the opinion to change it earlier, that is the safe bet. But what does changing redline gear oil earlier accomplish? The oil doesn't shear down and doesn't lose any performance with the heat ranges of light to medium duty. So when you change it, it will look cleaner, but unless the contamination is gritty you will have the same performance. Oil stop says running redline doubles the oil change interval for this very reason. One thing I would do, is really check the condition of the oil you are taking out, specifically look for any gritty material. If there is any gritty stuff, I would do 30k intervals until I did a change w/o gritty material. Get the dif warm before draining.

No: as some have proved over the last few years the electric four-wheel-drive systems seem to always be in motion even though the system is not engaged.

So there are some parts within the transfer case and front differential that are constantly moving and stirring around in the oil as well as ATF.

My question is and has not been answered yet how much stress is this oil and ATF going through every day even though the system is not engaged?
I do know within the transfer case the ATF gets pretty hot. Just by using a laser temperature gun and shooting the outside case as well as by touching with my hand for a split second.

I do not know that much about the front differential. As I approach 25,000 miles I will do my first service on this unit.

I cannot speak for anybody else but myself. But my four-wheel-drive system is only used 4 to 5 times a year max. Usually for only 5 to 10 miles at the Max.

Since I don't have any idea what type of abuse or stress these two fluids are put under on a daily basis when the four-wheel-drive system is not engaged I have to guess at a recommended service intervals.

I did change my rear end fluid at 10,000 miles and then at 20,000 miles I will now wait until 50,000 miles to change my fluid again. I did the two early services in regards to flushing out any break-wear metals which would end up shortening the life of the limited slip unit if left in

My transfer case I did the first service at 20,000 miles and will probably end up doing the next service at 40,000 miles then 60K. 2 quarts of RL is cheap & 15min is just piece of mind. Being this unit is fully functional with a clutch design instead of a chain driven--->changing the fluid out more frequently can only be a huge benefit.

For my front differential I am still really scratching my head. Like I said my first service will come at 25,000 miles I possibly could wait till 50-60K miles to do my next service.
Like I said I do not have any information on how much abuse and stress these two fluids are under when the 4WD system is not engaged.

why gears fail

Typical gear failures like wear, scuffing, micropitting and pitting are influenced by the oil temperature in the lubrication system. High temperatures lead to low viscosities and thus thin lubricant films in the gear mesh with generally detrimental influence on failure performance.

Temps in gears under regular load, 190F to 220F. Esters both cool the gears they will run cooler, and not shear down like their mineral cousins.