Kia Forum banner

DIY Transfer Case Fluid Drain

16K views 10 replies 7 participants last post by  rejesterd  
#1 ·
should be done every 15,000-30,000 miles.
this only pertains to AWD vehicles.

 
#3 ·
it has been discussed at great length, by many-many mechanics, skilled DIYers, and dealership shop employees - that todays owners manuals (specifically the service schedule) is more of a 'show & tell' piece for salesman, than actually a dedicated and reliable service schedule. these service schedules are designed to make cars appear as less maintenance, resulting in cheaper overall cost of ownership - than the next auto maker.

i have seen some crazy numbers coming out of manufacturer service schedules, including kia/hyundai 75,000 differential & transfercase fluid service, and other makers not even listing brake fluid a serviceable fluid!

transfercases & differentials use the same fluid, so its safe to say that both need to be changed about every 30,000miles for daily driver scenarios. if you tow, have a dirt driveway, drive on dusty roads, etc = bring that down to 15,000. if you drove into a puddle thats deeper than half the rim = drain both fluids.

every component has breathers, and they allow pressures to escape, and those breather tubes unfortunately allow moisture and dirt to get in.
 
#5 ·
absolutely; but not in this case.
any good, quality, seasoned mechanic; or someone who has spent time building race-only application race vehicles or race bikes can tell you, that owners manuals' service schedules are total crap. driven to make the vehicle appear as if its less maintenance than the competitor down the street. prime example: bmw's oil change interval of 15,000 miles = asinine

im not here to sell anyone, a service. im not here to convince anyone of anything. im only here to share knowledge. its your choice to follow it or not to. but any good quality mechanic, will tell you: differential & transfercase fluids shouldnt be driven more than 30,000 in solid axle vehicles, and 50,000 in cv-axle vehicles (ex: uni-body suv's). and if you drive on dusty roads, deep puddles, etc = 15-30k for all vehicles. deep flooded roads require immediate fluid drains. as i stated before, differentials & transfercases has vents - open:

Image
 
#9 ·
You should also post a video of differential fluid change.

So you just drained the transfer case and not refill as shown in video?
 
#10 ·
I am not sure that the differentials (transfer case, for AWD it's a central differential) will see such a heavy usage to need a drain earlier than 75k miles. I say this coming from my Ford Explorer AWD that has the rear diff with limited slip and is filled "for life" with Synthetic 75W140, central diff (transfer case) also with a Viscous Coupling (but lubricated by regular Mercon V ATF) and open front diff...

The transmission tough, is a totally different story. Friction bands wear and higher temperatures in stop-and-go traffic can really use up the additives in the fluid.
See attached how my 55k miles transmission fluid looked like in my new (to me) 2011 Soul. The owner manual says 105k miles.
 

Attachments

This post has been deleted