Originally Posted By: ryland
So the history on my element is at 35k I changed the atf once with z1. When I wiped off the magnant there was quite a bit of gunk on it. at 50k I changed with amsoil atf. On the magnant there was almost no gunk. At 60k I changed again with amsoil atf. There was a ton of gunk on the magnant. So now at 66k I want to do one more drain and fill with amsoil. Do you guys think that there will be a bunch of gunk? If there is I'll be kind of mad. The first time after I used amsoil I just wrote it off to "cleaning up" the stuff in there but if the magnant is really dirtly this time dont you guys think it would be because I'm getting more wear? I'm going to do it later this week. So any guesses??
My wife and I currently drive two Honda's, a 2006 Pilot and a 2007 Civic LX. We purchased both of these vehicles new. Prior to the Pilot, my wife drove a 1998 CR-V that we also bought new. Long story short, I have changed the ATF on all three of these vehicles.
I notice that you waited until 35K miles to perform the 1st drain/fill. Unless something has changed, doesn't Honda recommend ATF replacement every 30K miles? I bet the factory fill was dark at the 1st drain/fill. Honda states that dark Z1 does not equate to ATF breakdown or AT damage, but I never felt comfortable using it for more than 20K miles between drain/fills. As others have stated, a glob of metallic "sludge" on the drain plug's magnet is normal though.
As you know, one drain/fill replaces about 50% of the ATF in the system. The infusion of new Z1 ATF at 35K miles, and subsequent 15K mile drain interval, resulted in less "sludge" at 50K miles. This seems to validate (Subjective) my belief that Z1 should be used for no more than 20K miles.
After the 50K mile drain/fill, the ATF was essentially a 50/50 mix of Z1 and Amsoil ATF. I believe that the 50/50 mix of Amsoil & Z1 ATF cleaned some material that 100% Z1 ATF could not remove. This may explain the large accumulation of "sludge" during the short drain/fill interval between 50K and 60K miles.
My guess is that you will continue to see a lot of "sludge" until the residual Z1 ATF has been purged from the system. At that point, I believe the quantity of "sludge" will drop off, then equalize as the Amsoil ATF begins to maintain system cleanliness instead of removing accumulated deposits.
I use Amsoil ATF in both of my Honda vehicles and went through a very similar process. My recommendation is to utilize a 10K mile drain/fill interval on the current ATF. If there is a marked decrease in "sludge" at the next drain/fill (70K miles on vehicle), then I would increase the drain interval by 5K to 10K miles each subsequent drain interval. If there is still a lot of "sludge" at 70K miles, I would perform another drain/fill at 80K miles and contact Amsoil if the situation has not improved by then.