Does anybody have experience with changing the transmission oil on an ML320? Any links to helpful DIY websites? Any input is greatly appreciated!

 

Is it broken? If not.
Why fix it?

 

Broken? No, not at all! I just like to do preventative maintenance. Changing transmission fluid at about every 50k miles never hurts. There's no such thing as lifetime fluids, no matter what they say ...

 

Preventive maintenance apply to parts, that wear-out.
Glow pugs don't They burn occasionally, but till they do -they do 100% of the job. You might want to replace all the light bulbs, since they do wear-out.
No lifetime fluid?
Darn. Sounds, that adding only some transmission fluid to my 33 years old motorhome might be not good enough.

 

Not saying that your transmission will necessarily break down. It might just make things smoother. I know you don't have to change it on BMW's but a lot of people do anyway.
Views and opinons vary for the different car makes I guess ;-).

 

Luciano you are correct, there is no such thing as life time transmission fluid, even BMW. I was discussing this with my mechanic yesterday. He said BMW fluid is Dextron lll (I think) which is a GM fluid, and GM does not claim anything about lifetime. He was going to look it up for me but his Mercedes disk was scratched and would not read. When I find out something I will post it here. I have over 140 k Mi and I don't want my tranny to fail. Problem is if you fluid is over 100,000 miles they say if you replace the fluid the car wont make it off the lot because of all the detergents in the new fluid reacting with your old transmission gunk. I have heard this from several mechanics. Seems like "lifetime" fluid is just a way for MB and BMW to sell transmissions to 2nd or 3rd owners, as most 1st owners don't keep a car past 100,000.

Same thing holds true for 100,000 Mi spark plugs. Have you tried to remove a 100,000 Mi plug? There is a good chance it will strip the threads in that expensive aluminum head, and on a 320 you have 12 chances to strip threads. Hello new heads. And of course if you put on new heads you probably have fresh valves and springs which will not balance with your old piston rings so a whole new world of problems will unfold before your wallet.

 

Glow plugs and spark plugs are different things.
So did you have real experience with pulling the plugs on 320 engine smoother?
Our ML passed 60k and in about 3 years we will reach 100k on it. Shall I start to worry, or even try to replace them now?

 

Yes I pulled all 12 and it was a bitch. Here's why. After 100,000 Mi some boots are REALLY stuck to the plugs and because of the sharp angles and limited room, getting these boots off is a bitch. 2nd. the plugs were in there hard. I had to coax them out very carefully. My mechanic said I was very luck not to strip some of the soft aluminum threads in the head. I refused to replace the plugs (probably a mistake) instead I put some anti seize past on them and reinstalled them. Like I said, given the trouble it took to get the boots off them new plugs would have made more sense.

If you have less miles/years i would encourage you to get some anti seize on your plugs before the boots stick to the plugs and the plugs stick fast in your heads.
If anyone has a thought on how to keep the boots free and easy please share.

 

Changing the trans fluid is cheap insurance. I'd rather do that than have someone tell me I need to shell out $3500 for a rebuilt at 100k miles.

Driving style and city vs. highway use all impact how hot the trans fluid gets and how it oxidizes. On one of my cars, I change the trans fluid every year as the fluid is very dis-colored at the end of twelve months. I've been quite surprised by this but now keep an eye on it. Doing a rebuilt in this car would be out of the question - - it would cost more than the car is worth.

From my experience, city driving appears to be very hard on the fluid.

Take care.

 

The best insurance is get a new car every 2 years.
If you change transmission fluid, because you feel better, that is another story, but it still doesn't make technical sense to me.
As I mentioned in another thread, I knew the guy, who made 145,000 miles in his pickup with the same oil IN THE CRANKCASE.
There are lot of technical myths. At the time, when SE class oils in Europe were advised to run for 7 to 10 thousand miles, in USA the "Oil change 3000" was a prayer for each mechanic.
I translated that recommendation to "Easy money".
Anyway, I mentioned possibly the 30 + years old fluid in my motorhome. I decided not to change it for 2 reasons.
1. I have axially fluid filter, that I change occasionally
2. Transmission used to have a leak and over few months I added fluid close to its capacity, so it is about 1/2 replaced anyway.
This way, or another in the remodeling priorities transmission fluid was at the bottom of the list.
I started with the brakes.
30 years old tires with crack, that I could stick my fingertip into were the second
However... .I saved one of those tires on my tag axle just to prove the point.
My coach drives on commercial grade HD tires. Don't try that trick at home with passenger car tires.