When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Finally got around to doing the transfer case fluid change. It's probably the most "difficult" fluid service to do so far from a physicality standpoint. All said and done, start to finish, with lifting the car up, finding some tunes to listen to, figuring everything out, getting the tools I needed, taking pics and then dropping the car back down it took me 1hr & 10mins. Second time around I could easily split that time in half. So, I'd slot an hour or so of time out if you're planning to tackle this yourself.
These are the tools you'll need. Flathead screwdriver, 3/8" ratchet (long handle preferred), 12" 3/8" extension (or something in this range), drain pan and fluid. Honda's fluid is 75W-85, I used 75W-90 Full Syn (yes, it's fine). You can also add washers to the service.
If you're planning on using one of these nifty "squeeze packs" they sell now for diff fluid, the standard nipple is NOT long enough. I had to cut some nylon hose to extend it to fill the transfer case back up. If you don't, a lot of fluid will just pour out. Honestly, this may be one of the few times where a hand pump might have actually been the better route to go.
I did my best to take a pic of the fill plug. ALWAYS open the fill plug before you drain on any fluid service. You can see the nut right next to where the driveshaft inputs into the transfer case. With an extension, it takes a good amount of force to break this loose (hence why a long handle ratchet is preferred). You WILL need a long extension to be able to reach this nut because the crossmember in the foreground is in the way and there's really no space to get a stubby ratchet in there. Another note, this is much easier to access crawling under the car from the side (I went driver's side). The access point is pretty far back, so you'll be crawling quite a ways if you go from the front of the car.
Drain Plug. You will need to remove the underbody cover for the oil change side in order to access this plug. It's easy enough to get to. Easiest access point is from the front of the car. This is why this service was a bit more physical, crawling in and out from different points.
Just a picture of how I got the ratchet + extension on the fill plug. Again, easiest access is from the side of the vehicle. You can see why the long extension & handle is needed. The handle of my ratchet is almost right up against the crossmember. Extensions eat up torque, so it will take a good amount of force to crack her open.
And easy enough to do the drain plug.
Open the drain plug into your drain pan (it doesn't splash on anything, thankfully), button it up and then refill.
Looking at previous service write-ups, they used 33ft lbs on the plugs. I used the German standard of Gudentite-ft-lbs to secure both. As long as you're not cranking on them like a gorilla or limp-wristing them while tightening everything back up, you'll be fine.
If you're planning on using the squeeze pack, it's a bit of a chore to snake it in there and fill, but definitely do-able. Fill it slowly. If you fill too fast, you could get a false full reading (you fill until fluid exits the fill plug). Also, position your drain pan underneath to catch the overflow. Towels/rags will be needed to clean off the underbody. Once again, Acura did a good job engineering this as it doesn't get too crazy dripping on stuff. It still gets places, but nowhere near as bad as some.
As an aside, I found fluid weeping from where the transfer case mates to the transmission. When I pulled the drain plug, the fluid did seem low. Yes, 0.61qts is nothing, but it seemed like there wasn't even that much in it. The car has 21k miles on it. Stupidly, I wiped it all down without snapping pictures. I'll have to monitor during future fluid changes to see if it's going to be an issue. Just something to look out for ... or, if you don't do the service yourself, something to mention to the service department to see if its an issue. I'm sure they'll tell you it's normal ... until your warranty runs out, of course.
Great write up @leomio2.0 . Even if I still had my RDX, I wouldn't be doing this, for two reasons. Mine was FWD, and sadly, I am no longer able to get down and under cars.
Great write up @leomio2.0 . Even if I still had my RDX, I wouldn't be doing this, for two reasons. Mine was FWD, and sadly, I am no longer able to get down and under cars.
LoL. Yes, SH-AWD only, in case someone with FWD goes looking for their transfer case.
I'll enjoy wrenching on my car as long as my lower back can tolerate it. Seems like the days are numbered, sadly.
Finally got around to doing the transfer case fluid change. It's probably the most "difficult" fluid service to do so far from a physicality standpoint. All said and done, start to finish, with lifting the car up, finding some tunes to listen to, figuring everything out, getting the tools I needed, taking pics and then dropping the car back down it took me 1hr & 10mins. Second time around I could easily split that time in half. So, I'd slot an hour or so of time out if you're planning to tackle this yourself.
These are the tools you'll need. Flathead screwdriver, 3/8" ratchet (long handle preferred), 12" 3/8" extension (or something in this range), drain pan and fluid. Honda's fluid is 75W-85, I used 75W-90 Full Syn (yes, it's fine). You can also add washers to the service.
If you're planning on using one of these nifty "squeeze packs" they sell now for diff fluid, the standard nipple is NOT long enough. I had to cut some nylon hose to extend it to fill the transfer case back up. If you don't, a lot of fluid will just pour out. Honestly, this may be one of the few times where a hand pump might have actually been the better route to go.
I did my best to take a pic of the fill plug. ALWAYS open the fill plug before you drain on any fluid service. You can see the nut right next to where the driveshaft inputs into the transfer case. With an extension, it takes a good amount of force to break this loose (hence why a long handle ratchet is preferred). You WILL need a long extension to be able to reach this nut because the crossmember in the foreground is in the way and there's really no space to get a stubby ratchet in there. Another note, this is much easier to access crawling under the car from the side (I went driver's side). The access point is pretty far back, so you'll be crawling quite a ways if you go from the front of the car.
Drain Plug. You will need to remove the underbody cover for the oil change side in order to access this plug. It's easy enough to get to. Easiest access point is from the front of the car. This is why this service was a bit more physical, crawling in and out from different points.
Just a picture of how I got the ratchet + extension on the fill plug. Again, easiest access is from the side of the vehicle. You can see why the long extension & handle is needed. The handle of my ratchet is almost right up against the crossmember. Extensions eat up torque, so it will take a good amount of force to crack her open.
And easy enough to do the drain plug.
Open the drain plug into your drain pan (it doesn't splash on anything, thankfully), button it up and then refill.
Looking at previous service write-ups, they used 33ft lbs on the plugs. I used the German standard of Gudentite-ft-lbs to secure both. As long as you're not cranking on them like a gorilla or limp-wristing them while tightening everything back up, you'll be fine.
If you're planning on using the squeeze pack, it's a bit of a chore to snake it in there and fill, but definitely do-able. Fill it slowly. If you fill too fast, you could get a false full reading (you fill until fluid exits the fill plug). Also, position your drain pan underneath to catch the overflow. Towels/rags will be needed to clean off the underbody. Once again, Acura did a good job engineering this as it doesn't get too crazy dripping on stuff. It still gets places, but nowhere near as bad as some.
As an aside, I found fluid weeping from where the transfer case mates to the transmission. When I pulled the drain plug, the fluid did seem low. Yes, 0.61qts is nothing, but it seemed like there wasn't even that much in it. The car has 21k miles on it. Stupidly, I wiped it all down without snapping pictures. I'll have to monitor during future fluid changes to see if it's going to be an issue. Just something to look out for ... or, if you don't do the service yourself, something to mention to the service department to see if its an issue. I'm sure they'll tell you it's normal ... until your warranty runs out, of course.
Are front differential and transfer case are the same?
08-25-2022, 11:15 AM
