Aside from possoble internal differences, which ford is notorious for, I would bet that the trans in a truck with a smaller motor works just as hard at its max towing as a truck with the big v8 does at its max towing capacity.

I'd be willing to bet that the trans does more work in an empty truck with the smaller motor than with the big.

Just my thoughts

 

Trans fluid wears even at lower loads. And it is much less complicated to recommend the same service intervals for one transmission model then to make different intervals for different engines tied to the same trans.

The fluid wears most in the torque converter. When the converter is open it is working the fluid hard, and that breaks the long chain molecules into smaller molecules. When enough of this happens the fluid must be changed.

 

Hi Mark! I wonder what your take is on the thread in the original post. I posted in it that I thought 150k (as recommended in the manual) was WAY too long, and could result in a 10 to 15 year change interval, depending on how many miles driven per year. I plan on doing a pan fluid/filter change about every 50k/3-4 years. I know that doesn't change all the fluid, but my plan of doing the pan change as mentioned would keep the fluid fairly clean over the life of the transmission. Thoughts?

 

The transmission on trucks with the 3.7L have two less clutches. I'm not sure which clutches or how this would affect fluid wear.

 

Do what you propose. The fluid change intervals are at least partially driven by Consumer Report's cost of maintenance. Longer intervals results in a lower cost.
I doubt that. I'll bet they have two less clutch plates in one or more of the clutches. But to have two less clutches would require a transmission redesign.

They way it affects fluid wear is that each clutch plate is doing about the same amount of work in the smaller engine as those in the larger engine with more plates.

And you don't want more plates in the smaller engine. It might make it last a bit longer, but the shifts are going to be uncontrollable. There will be too much torque capacity gain with the smaller torque input. That's why the clutch plate count has to go down with smaller engines.

 

All of the car builders are using a version of a lifetime fluid in their transmissions. I know the Tundra has a recommended 100K mile flush cycle as opposed to Ford's 150K.

 

Yes, Mark I should have said clutch plates. I didn't know why but what you said makes sense. I figured it was just cheaper and with the smaller engine Ford didn't see the need for the extra plates.

 

The transmission is still moving a 5000 pound truck around no matter what engine is turning it. Transmission work/output is the same on an empty truck.

150K is ridiculous to me. I like 50K-100k at most for Trans fluid changes.

 

Thanks for bringing this up. This is the EXACT reason my transmission fluid will not be in my truck for as long as specified in the manual.

Sorry for deviating from your original question Tim.

 

No, no, it's cool. Keep the discussion going.

 

How often to transmissions fail because clutches wear out? Not talking about when something else fails and takes the clutch with it.

 

They will eventually reach end of life where the clutch material has worn off. Normally that's above a quarter million miles.

 

I don't think he's saying that as an endorsement for the long interval. You might want to re-read that statement carefully...

 

I am at 58,xxx miles on my 2012 F150 5.0 4x4 and just scheduled a routine service with my nearest dealer. They asked if I wanted to do the 60k mile service which includes a "transmission fluid exchange". I asked how much the fluid change added to the bill and they quoted me $265.

I searched but have not really found a consensus for when to change it. With my past vehicles I have always followed somewhere between the normal and severe service schedules but did not see any mention of changing the fluid earlier than 150,000 miles for any of the service schedules in the owners manual.

I also find it interesting that they are recommending the transmission fluid change so early, but not Spark plugs or Transfer case fluid, both of which are in the severe service schedule.

Now that these trucks are starting to run up higher mileage has anyone had any experience waiting until 150,000 to change or changed earlier with good or bad results? I am guessing the quote for the change is on the high side but I also know the fluid is not exactly cheap.

I am most likely just going with the usual Oil Change, Tire Rotation, and inspection this time. I have an air filter waiting to go in a home so that should have me covered at 60k for the normal maintenance schedule at least.

 

Woops, I thought I was in the 2009-14 forum when I created this. Feel free to move this.