Recommended service?

If it's not in the manual, it doesn't need to be done.

Echo most of the comments thus far.
FYI, a pan drain and fill on the trans gets only about 1/2 the fluid.
Either multiple iterations of do a complete drain/fill if you want a true trans service.

The most I would do at 8 years old and 55k Miles is the trans, brake fluid and rear diff.

dodge guy wrote:
The most I would do at 8 years old and 55k Miles is the trans, brake fluid and rear diff.

rear diff? Does the owners manual call for it?

I've never changed any rear diff oil on any vehicle, except on what is now my DD. Only reason I did that was to get rid a slight gear whine.

Your truck came with a very valuable feature....the owner's manual. In it you will find every recommended service and at what intervals those services should be performed. Since it was written by the people who designed and built your truck, it should be the only source considered for information about service procedures. Always remember, the service writer works on commission, and the technicians only get paid when they work on a vehicle, so their interests are in selling services, often times unnecessary services.

Exactly what I've done on my 2008 Duramax with 80,000.
Done at a local shop that follows the manual. Never tries to get me to do other services on it.

jrs1871 wrote:
T.......If we had done all the flushes they were pushing, brake fluid, power steering, fuel system and engine coolant, it would have come to nearly $1,000. Personally, I have never heard of flushing brake fluid or power steering unless you have had some incident that caused a break in that system.

Honestly this was sound advice from the dealer. I know it sounds like a money grab. I do all my own work so I'd only be out about $50 in supplies. You might be able to find a shop that would do all this cheaper, but the takeaway is that the dealer was trying to help you properly maintain your truck for longer life of the components.

Coolant
Dexcool has a rated lifetime of 5 years or 100,000 miles....WHICHEVER COMES FIRST. If the organic acids in your coolant become oxidized they will create a sludge that can cause blockages in coolant passages. That's really bad and causes major problems, right? Since your truck is 8 years old you are past due if this has never been done

Brake Fluid
Brake fluid is hydroscopic, meaning it will draw moisture. Over time the collection of moisture and contaminants in your brake fluid degrades the compressibility of the oil and decreases your braking capacity. This has nothing to do with a 'break in the system'. Siphon some fluid out of your master cylinder then compare it to fresh fluid. You'll see the difference quickly. In my opinion a brake system should be flushed every 2-3 years.

Power Steering Fluid
In your truck it not only does the job of turning the tires on your truck that weighs more than 3.5 tons, but it also your only means of powering the booster on your brake master cylinder. There is no vacuum on a diesel engine, thus they rely on 'hydroboost' to create power brakes. So, if the power steering fluid/pump fails you also lose power brakes. Doesn't sound too fun to me towing a large RV.

Power steering fluid is cheap. Also, old contaminated fluid has less lubricity and therefore can allow more wear on pump parts. To me it's cheap insurance and preventative maintenance to flush the fluid every couple of years.

KJ

Injector clean is a money grab. The other services yeah those are legit although a lot of people don’t do it. I’m a little more conscientious than some and do change coolant, brake, ps, diff fluid at 100k or sooner depending on what it is.
Coolant and diffs are straight forward. I’m not motivated enough to flush bleed brakes or drain power steering, but for a few more bucks and a lot less time, you can suck the reserviours for both out multiple times and capture most all the old fluid.
For ps, can do it with just starting the car for a min between rounds. Brakes, I do it repeatedly with some miles in between to ensure the new fluid mixes thoroughly with the old.
Say you get 50% of the total each time. That’s 50-75-87.5-93.5% after you’ve done it 4 times.
Basically as good as any oil change gets.