Advice on PTU, Differential, Transmission fluid change on ST

[Samurai Edge]

13 hours ago, enigma-2 said:

Oh sure, go ahead, laugh ....

https://a.co/d/fXTsoGN

 

<snort>

Well, the Japanese do things differently than we do in the US.    🫠

[Samurai Edge]

1 hour ago, garycrist said:

On RDU failure. It looks like the pinion bearings are failing due to fluid break-down due

to excessive heat. It is tough to figure out if they do light weight fluids for EPA crap.

Bearing clearance on rotating parts has not changed. Clutch pack clearances are the same.

Hence, the tighter clearances B.S. that is fed to us, is not a starter nor valid! 

 

Before the recent push to maximize fuel economy, lower emissions especially CO2, a heavier 

weight differential fluid ie. 75-140 etc. was called for for heavy duty service or towing.

Remember, Domestic manufactures sell new vehicles. The faster your new pride and joy wears

out, the faster the bastards can sell you a new one. 

 

 

 

 

 

r

 

Overall, I don't disagree with what you are saying, hence my belief to change fluids at a faster rate than OEM usually recommends.

 

Could all be due to meeting certain EPA mileage requirements ( thinner oil = less resistance = easier turning = less fuel used ) but I don't have access to the knowledge base that designed the Disconnect RDU and why Ford states only 75W for this RDU.  That's why I'll stick to the recommended 75W for the RDU until I see more, certified information on switching to a thicker gear oil.

 

Same goes for the PDU.  However I would not use straight Redline Heavyweight Shockproof ( Film thickness greater than an SAE 75W250, yet low fluid friction like 75W90 )

in the PDU as some have suggested.  That stuff is designed to cling to metal and use only in splash boxes.  Read multiple reports in the past of people who have used Redline Heavyweight Shockproof in their gearbox and when they took it apart, they found a thick sludge of " Smurf Blood " packed in around the gear case that had to be removed.

 

Redline Lightweight Shockproof is a 75W80 so I would definitely consider using that in the PTU.  Always worked great in my 5spd and 6spd with zero issues and smoothed out the shifting

[Samurai Edge]

Just an update on the Disconnect RDU gear oil:

 

Ford Recommended Gear Oil = Motorcraft Rear Axle Oil - XY75WQL  at a mere $32.99 on Amazon.

 

I just got off the phone with Redline Technical Service.  According to Redline, their corresponding oil will be Red Line 50604 MT-LV 70W/75W GL-4 High-Performance Full Synthetic Gear Oil Lubricant for Manual Transmissions & Transaxles - 1 Quart. for $22 on Amazon

 

Nothing apparently available from Motul.  

Just an FYI for those interested.

 

Also Note:  While it's true as stated by someone earlier, Ford can't deny you ( allegedly ) any claim if you use Ford Recommended products.  However, in reality, the manufacturer can't deny a claim as long as you use the appropriate grade product, IE;  if you use a comparable 5W-30 motor oil other than Ford product, all else being equal, they can't deny you.

 

Just remember to use quality products, not some cheap version from Walmart, etc.

 

 

[enigma-2]

First of all, Ford definitely can deny you warranty coverage by making you prove that the lubricant used is equal to the one they recommend. Assuming that they PTU lubricant is actually the US Lubricants, 300 Waylube, your Redline won't measure up (it's why is so much less expenseve.) But it may be sufficient. 

 

Don't take the word of a competitor. Get it in writing from Ford. For example, i refused to allow my local Lincoln dealer to switch my MKX from yellow coolant to the new green; until I got a printout of an email from the local Ford district administrator.