I have 20k on my car and decided to change the diff and trans fluid to get ready for Thunderhill. I was surprised at how dirty the rear diff fluid was. It was dark grey/brown with lots of metal shavings on the magnetic plug. I was surprised because I changed diff fluid on a Mazda 323 with 80k and it came out as clean as the fresh fluid. I replaced the fluid with Castrol Syntec gear lub. I then changed the transmission fluid with Honda MTF (no one heard of MTF-2 at the Honda parts counter, and it didn't come up on the computer). That also came out dark grey/brown. I immediately felt the difference in shifting after the change. A lot of the clunckyness is gone, and there seems to be more "cushion" when shifting into gear, but still feels just as precise. I was surprised to feel such a difference. I had the clutch TSB done at about 9k so this fluid only had about 11k on it.

 

Is it hard to change diff and trans fluid your self?? Does it require any special tools??

 

https://www.s2ki.com/forums/showthread.php?...&threadid=54614

 

I have access to a lift, so it was very easy. It's doable with the car on jack stands, but much less comfortable. The rear diff requires a 24mm socket and 23mm box or open end wrench (you cant get a socket onto the fill plug because there is a brace just behind the diff). For the transmission, the drain plug requires a 3/8" socket wrench (no socket attached) and the fill plug I think was a 17mm. The only other gadget needed is a pump to pump out the fluids form the bottles into the fill plugs. Most carpart and marine part stores will have this.

 

Honda recommends changing the diff fluid every 15k, The rumor i heard when I bought one is that it is a mazda rear. I had an 86 rx7, which coincidently needed the rear diff done every 15k.

 

Honda recommends changing the diff fluid every 15k, The rumor i heard when I bought one is that it is a mazda rear. I had an 86 rx7, which coincidently needed the rear diff done every 15k.

 

My anecdote:
Changed the diff fluid on mine for the first time at 16K, and it was truly filthy: dark grey, almost gloppy, and the magnetic plug must have had 3mm of gunk on it. Put in Mobil 1 75W90, car felt fine, but I decided to change that out, too, after only a week (sort of a "flush"). Indeed, to my surprise, it also came out quite grey (was originally a clear golden color)! Very little gunk on the plug though, as hoped/expected. Now I have Redline Shockproof Heavy... car's again running fine -- no noticeable difference from the Mobil 1... Guess we'll see how it pans out.