5R55 oil analysis info from Blackstone labs-

[hertfordnc]

My 2004 XLT has 187,000 miles, probably has original ATF.

So I wanted to know if a fluid analysis would be useful in guessing how much life might be left in it.

I wrote to Blacksone labs and got this excelent response.


Hi Dave,

We would of course be able to quantify our findings if you sent in a
transmission sample to us. The tricky bit is, though, that it's still the
factory fill ATF, which means metals will likely be on the high side from
lingering break-in left over from when the transmission was new, plus
normal accumulation over the past 190,000 miles. That can make it difficult
for us to say if your transmission does indeed have a problem, though if a
bushing has failed, we might expect copper (rather than aluminum) to read
even higher than we'd expect for break-in.

Since the transmission is running fine for you, our suggestion would be to
change out the factory fill, and then sample the next fill after about
30,000 miles or so to see how things look. We do indeed have a good
baseline established for these 5R55S transmissions, and that suggested
30,000 miles is about the average change interval for them.

Sincerely,

Clair Pranger
Blackstone Laboratories
416 E. Pettit Ave.
Fort Wayne, IN 46806
(260) 744-2380

 

[Blue m&m]

Dear lord. How have you gotten that kind of mileage on the original fluid?

 

[hertfordnc]

Dear lord. How have you gotten that kind of mileage on the original fluid?

I don't know for sure but we bought it around 100K and put another 90,000 on it. maybe it got flushed every 30K, maybe it failed and was replaced. But I'm assuming nothing was ever done.

 

[ROBinGa]

My 2003 4.6 4x4 has 177k miles on the original trans fluid and filter. I bought a new filter couple years ago and an adapter for the fill plug, but am taking that “if it ain’t broke don’t fix it” approach at this point. It’s been fine - knocks wood- so I don’t want to risk any changes.

 

[Albino 94LTD]

Blackstone is a top notch company. They don't just send the report, they include their interpretation of the numbers..

Great company.

Send in motor oil samples too

 

[Number4]

220k on my 2004 4.6l 5R55S. All original.

Only got 99k on my 4.0l 5R55S.

Too afraid to do any fluid changes.

 

[hertfordnc]

If this was just me daily driver i would not worry about it but i want this truck for road trips and excursions deep in the woods. I want to know the trans has some years left in it.

Oil analysis is only $25 and they can tell you a lot of stuff. Apparently, the failure point for these trannnies is the servo bushings. The amount of aluminum and copper in the oil will provide a good indication as toe how worn they are.