[kentlawrence]

Is it possible to get transmission fluid coming from the inner axle boot? Driver side. I have a dark runny fluid coming from
the inner axle boot on my 2006 Sienna. 75k miles. It's too dark to tell if its the purple fluid from the transmission. I'm guessing its
because its mixing with CV joint grease before it spills out. I can't see any cracks in the boot, but I'm thinking tranny fluid
could get through a boot where CV grease might not. Is this common? What am I looking at here, a new half shaft or is
there some kind of seal between the joint and the transmission that is letting fluid out?

 

[thanwu]

You should be able to see some pink deposit above the axle if it is transmission fluid. But personally I have never experience transmission fluid at the location. You need to get down your vehicle and check it with a white paper towel. It should be very easy to tell if it is transmission fluid or other oil.

 

[kentlawrence]

You should be able to see some pink deposit above the axle if it is transmission fluid. But personally I have never experience transmission fluid at the location. You need to get down your vehicle and check it with a white paper towel. It should be very easy to tell if it is transmission fluid or other oil.

Thanks. I changed my mind about transmission fluid coming from the boot. I've looked into it more and that isn't possible. It is spilling off the boot. I believe its just an axle seal gone bad. My van has 75k miles on it and I have never changed the transmission fluid. I know. Stupid. I'll be taking care of that this weekend. That's probably why its so dark. It's dirty and in need of replacement, so I'm asking for problems like failing seals and who knows what else up there in the tranny.

 

[fibber2]

Remember that power steering fluid and transmission fluid are close cousins. Steering rack failure and fluid making it way to the steering boot, rotting it and leaking out and dripping down onto the front CV boots is a known issue with these vans. So your observation might be close to correct.

 

[kentlawrence]

Final diagnosis: I detected a fine split in the inner axle boot. What I saw leaking was just the grease in the boot after 75k miles of getting churned up in the joint. It was runnier than I thought it should be, but there are no bad axle seals. It's bone dry right there. I did notice that the dust boot on
the steering rack was open and flopping around, but no fluid was leaking from the rack. I'll clean that up and put a boot on there too. I wish they would make these boots last longer. This will be the third boot on the steering rack in 75k miles. The drive shaft boots are lasting much longer than the steering boot, which doesn't make much sense to me. Thanks for your suggestions!