Zumkopf

So I finally finish replacing the valve body on my 98 D2 4.2, and start refilling the transmission with (expensive) honey-colored Pentosin. Fill the pan, start the car, keep pushing in the fluid. Seven liters in, the fuel pump starts moaning, the car stalls, and fluid starts pouring back out the filling hole. I rush to stuff the plug in and realize to my horror that the spilling Pentosin is milky-white-tan. The car won’t restart, won’t even crank. I put the battery charger on and let it cool off. It then restarts but the alternator light is on and revving the motor doesn’t put it out.

i figure I have three problems: (1) the radiator is shot, (2) the alternator is shot, and (3) I have to buy about 16 liters of Pentosin, and do at least one complete flush cycle. My questions: Does it sound like I’m right, or am I overlooking other explanations? Can I replace the radiator without taking the whole front end off? Can I replace the alternator without taking the front end off? Do I have to drop the trans pan and replace the filter again, or will the flush cycle be enough to clear it out (seeing as it’s brand new)? Can I use something cheaper than Pentosin for the first flush?

They say that what doesn’t kill you makes you stronger. This A8 is going to make me a mighty, mighty man.

Zumkopf
1998 Audi A8 Quattro 140k

hillpc

Ouch! I had the trans fluid gush out on me when the melted insulation on the crankshaft position sensor wires caused them to short and shut down the car. You gotta find out what caused your shutdown too.

I have changed a seized alternator without talking the front end off, but if I had to do it over again, I'd probably take the front end off. I had to inspect my A/C condenser recently to find its leak, and took off the front end for that. On a lift it's not too bad, just a few bolts, though corroded fasteners are always a potential snafu. I can't imagine getting the radiator out without taking off the front end. OCLES, in a post on this forum, has made a convincing case to "just follow the instructions" instead of trying to work around them and skinning knuckles, cursing, etc, though I admit that sometimes the instructions seem awful heavy-handed on removing stuff. I have worked both ways and have to make a choice each time, as it's not obvious which way works better, in my experience so far. We don't all have the facilities and tools that the service manual assumes.

There are many threads about the trans fluid. I have switched from Pentosin to the much cheaper Valvoline Maxlife. You can see a short debate about this topic at https://www.audiworld.com/forums/a8-...-area-2939729/

I don't know anything about flushing trans fluid. Will you be using machinery of some sort?

jfrahm

The alternator is easy enough from below with a flex head ratchet and maybe some extensions for your allen bits.

I have been using MaxLife ATF for a few years. Meets the spec, probably far better than the old semi-synth the spec was based on.

hillpc

I concur, Joel. The alternator itself was very easy to get out from below, especially since I simply cut the belt off. It's access to the belt tensioning stuff that had me cursing.

Zumkopf

hillpc

I can't speak to that. Think I've seen a homemade flush procedure somewhere on one of these forums.

I had the manual valve jam on me after trans warmed up (after the car had sat for 5 years), not letting me put it back in Park once I had driven it around the block. The guy I bought a new one (as well as other trans parts) from, told me the plastic ones absorb water and swell. So if you run into that down the road, that's a possible reason, with you having milky fluid now.

Thread at https://www.audiworld.com/forums/a8-...drive-2891020/

jfrahm

It's tough to get the ATF out of the torque converter (where most of it lives) unless you rig up a way to flush via the cooler lines. Like a big funner in one line and a jug under the other. It'll move about 3 gallons but you can stop and start.
I think the ATF is hard on the paint and clutches? You may need to also drop the valve body and clean stuff out.