Causes for grenaded T-case?

[lil_Blue_Ford]

I’m guessing the silver colored fluid that was drained indicates something going severely wrong. No fluid should be silver. The silver color was likely caused by metal particles in the fluid. A whole ship ton. There’s likely a lot of carnage in that case.

I‘ve always used Dex/Mercon III in the 1350 and 1354 cases. That was original spec to my understanding. I fill until it starts dribbling out the fill hole, just like a differential. Technically it’s supposed to be under, but it’s easier to just go until it starts dribbling.

 

[m.dolomieu]

I’m guessing the silver colored fluid that was drained indicates something going severely wrong. No fluid should be silver. The silver color was likely caused by metal particles in the fluid. A whole ship ton. There’s likely a lot of carnage in that case.

I‘ve always used Dex/Mercon III in the 1350 and 1354 cases. That was original spec to my understanding. I fill until it starts dribbling out the fill hole, just like a differential. Technically it’s supposed to be under, but it’s easier to just go until it starts dribbling.

I'll document the carnage when I pull it

 

[pjtoledo]

the locating tab on the pump likes to chew things up, and it's right where the failure is.
did the silver stuff stick to a magnet?

 

[19Walt93]

What is the correct fluid these days for a transfer case on these trucks? The tech pages say Mercon ATF, which I assume is Mercon V or equivalent? Or should I be using XL-12?

Also, I put brand new BF Goodrich KO2s 31x10.5 as the truck had from the factory, but I will double check that I didn't put the wrong size on somehow. Definitely going to inspect the u-joints when I get the truck back too.

If it's Ford's transfer case fluid number, XL-12 is Mercon/Dexron III spec not Mercon V. Valvoline Mercon/Dexron III meets the same spec for less money.
As long as all 4 tires are the same diameter- Ford spec is no more than 3/8" difference in circumference- you should be fine.

 

[sgtsandman]

What is the correct fluid these days for a transfer case on these trucks? The tech pages say Mercon ATF, which I assume is Mercon V or equivalent? Or should I be using XL-12?

Also, I put brand new BF Goodrich KO2s 31x10.5 as the truck had from the factory, but I will double check that I didn't put the wrong size on somehow. Definitely going to inspect the u-joints when I get the truck back too.

The newer, old Rangers call for Mercon V for the transmission and the transfer case. Before then, it was Mercon III or an ATF based transfer case fluid. I'm not sure when Ford did the switch.

From personal experience, my manual transmission doesn't like the aftermarket Mercon V compatible fluids but the transfer case never seemed to care. Shifting the transmission would get rough and difficult to shift way sooner than it should have with aftermarket but would return to normal once actual Mercon V was put in it. Your's might be different.

From the description of the fluid that came out of the case, it sounds like something was on it's way out.

As far as the tires, they wouldn't have caused a problem. I have 31X10.5R15 tires on my 2011 and never had a problem. Others had done the same with few problems.

 

[00t444e]

Mercon LV is not the correct fluid, it takes regular Mercon rated ATF, the cheap ATF found at Walmart or any other parts store is Mercon rated. However I doubt that is what caused your failure, was it ran low on fluid before?

 

[lowspeedpursuit]

Per motorcraft.com right now, Mercon LV is the current spec for t-case fluid, and Mercon V is not.

I still put Dex/Merc in everything, because Merc vs. LV to me feels like 5w-30 vs. 5w-20 all over again. Something was built with the older, thicker fluid in mind, and spec was updated to the newer fluid for CAFE reasons. Thinner fluids must test "good enough", but for my money and peace of mind, I'll stick with the original design.

Point is, preferences aside, LV isn't right-out "incorrect".

 

[m.dolomieu]

Mercon LV is not the correct fluid, it takes regular Mercon rated ATF, the cheap ATF found at Walmart or any other parts store is Mercon rated. However I doubt that is what caused your failure, was it ran low on fluid before?

It's hard to say since I only have about 300 miles of the 180k on the truck. It's not entirely impossible that I spilled fluid out of the breather connection in the 4ish months of shuffling the case around my garage while I was rebuilding the trans. Hindsight tells me I should've double-checked fluid level before taking it for a spin. Picked up a 94k mile t-case and some Dex/Merc fluid today. Going to check the drive line, but hopefully I learned my lesson.

 

[m.dolomieu]

Per motorcraft.com right now, Mercon LV is the current spec for t-case fluid, and Mercon V is not.

I still put Dex/Merc in everything, because Merc vs. LV to me feels like 5w-30 vs. 5w-20 all over again. Something was built with the older, thicker fluid in mind, and spec was updated to the newer fluid for CAFE reasons. Thinner fluids must test "good enough", but for my money and peace of mind, I'll stick with the original design.

Point is, preferences aside, LV isn't right-out "incorrect".

I picked up 2qts of Valvoline 789153, hopefully that is the correct stuff.

 

[ekrampitzjr]

the locating tab on the pump likes to chew things up, and it's right where the failure is.
did the silver stuff stick to a magnet?

If it's noticeably silver, it's probably fine aluminum particles that wouldn't stick to a magnet. Now it gets interesting. The case is probably aluminum, but most of the guts inside that rotate are probably steel. This was the pattern with Mazda transmissions when I worked for that company's reman operation.

 

[m.dolomieu]

Silver glitter did not overwhelmingly stick to a magnet when I waved it through the fluid as it was sitting in an oil catch pan. The truck should be done at the body shop tomorrow, so I may know more this weekend.

 

[superj]

I was going to ask if you found a tcase because there are two on marketplace around me, but i see you found one

 

[sgtsandman]

Per motorcraft.com right now, Mercon LV is the current spec for t-case fluid, and Mercon V is not.

I still put Dex/Merc in everything, because Merc vs. LV to me feels like 5w-30 vs. 5w-20 all over again. Something was built with the older, thicker fluid in mind, and spec was updated to the newer fluid for CAFE reasons. Thinner fluids must test "good enough", but for my money and peace of mind, I'll stick with the original design.

Point is, preferences aside, LV isn't right-out "incorrect".

Mercon LV is not backward compatible as per the link you provided. If the original spec was for a previous Mercon product, LV can not be used. As far as I know, 2019 was the first year that LV was specified as the proper fluid for the transfer case in a Ranger. I can't speak for non-North American market Ford Rangers.

 

[sgtsandman]

I picked up 2qts of Valvoline 789153, hopefully that is the correct stuff.

I would carefully read the label and compare it to what Valvoline's web site says and compare what specifications it says it meets compared the the specifications the motorcraft site list for the fluid. From my quick search using the brand and number you gave, CVT fluid came up a lot.

 

[lowspeedpursuit]

Mercon LV is not backward compatible as per the link you provided. If the original spec was for a previous Mercon product, LV can not be used. As far as I know, 2019 was the first year that LV was specified as the proper fluid for the transfer case in a Ranger. I can't speak for non-North American market Ford Rangers.

Can you point me to the right place on the page? I'm not seeing it.

Like I said, I don't actually use LV either, but the page says "For use in all transfer cases", and then it lists a bunch of non-compatible fluids, but none of them are original Mercon or XL-12.