Since I did the tuner stuff I figured I would do a little more.

I tow an 11k lbs boat and about the same travel trailer. Not often enough but at 46k miles I thought it was time to take care of rear differential.,

First the manual says not to change it unless it is submerged in water and water intrusion.

Second the manaul says 6.9 pints or 3.5 quarts. I read somewhere some people saying two quarts.

I plan to use either mobil 1 or royal purple. Same price of $20 at parts store.

I have an F250 with LS differential.

 

Don't bother till 60K miles is what I did and I tow 14K very often.

 

Launching the boat may be grounds for changing it earlier than recomended. Do you submerge the axle while launching?

 

In the Ford diesel supplement, F-Super Duty, normal scheduled maintenance:

50,000 miles (80,000 km)
❑ Change engine oil and replace oil filter
❑ Rotate tires, inspect tires for wear and measure tread depth
and inspect wheels for endplay and noise (vehicles with dual
rear wheels should only rotate if unusual wear is noted)
❑ Inspect air filter restriction gauge, replace filter as required
❑ Change rear axle fluid (DANA axles only. Refer to Special
Operating Conditions for more information)
❑ Lubricate steering linkage, ball joints, suspension, tie rod
ends, drive shaft, 4x4 front axle U-joints and U-joints (lubricate
if equipped with Zerk fittings)
❑ Perform multi-point inspection (recommended)

 

Thanks for the input. My rear tires are about the only thing that might touch water launching the boat.

How do I know I have a dana rear end??

 

Rear axle isn't a dana unless its a 450 or 550, everything else has the sterling.

 

I believe the Ford axle is only used on the F250, and the Dana 80, 110 and 130 are used on the F350 and up.

http://wpnet.us/Rear_axles.pdf

 

I thought all the DRW trucks had Dana's?

 

Dana axles are used on the F350 DRW at least (I have one), not positive on a F350 SRW.

 

my 2010 350 is a sterling....

 

sterling on the f250/350 srw

 

350 srw.

drw has dana.

 

You guys get the idea!

Unless you have a DRW truck there is no such thing as a specified drain interval. Of course we all know that lube doesn't last forever, and therefore most of us like to change ours at least so we have something to do.

That being said I don't like throwing out good lube, so I suggest waiting until at LEAST 60,000 miles before a change. There's nothing you can do to that axle that will cause it to consume lube any faster.

 

Normal Vehicle Axle Maintenance
❑ Rear axles and power take-off (PTO) units containing synthetic lubricant and light duty trucks equipped with Ford-design axles are lubricated for life. These lubricants are not to be checked or changed unless a leak is suspected, service is required or the axle assembly has been submerged in water. The axle and PTO lubricant should be changed anytime the axle and PTO have been submerged in water. During extended trailer tow operation above 70°F ambient and wide open throttle for extended periods above 45 mph, non-synthetic rear axle lubricants should be replaced every 3,000 miles or 3 months, whichever occurs first. The 3,000 mile lube change interval may be waived if the axle was filled with 75W140 synthetic gear lubricant meeting Ford specification WSL-M2C192-A, part number F1TZ-19580-B or equivalent. Add friction modifier C8AZ-19B546-A (EST-M2C118-A) or equivalent for complete refill of Traction-Lok rear axles (see Owner’s Guide for quantity). The axle
lubricant should be changed anytime an axle has been submerged in water.

 

My 2008 F-350 4x4 6.4l DRW has a dana 80 Axel, I'm 100% positive. I would remove the level check plug (the plug is magnetic so look for metal shavings) And dip your finger in the fluid if you cant touch the fluid its way to low. If you can touch the fluid and its really dark such as used engine oil change it. Also check your pinion seal for leaks if your fluid is low, If there is a lot of metal shavings on the plug get the rear end flushed and serviced.