Changed engine oil for the first time in the new truck this weekend and replaced spin-on Allison filter... My heart totally sank, because the fluid that drained out when I pulled the spin-on was unrecognizable as having come from a transmission. Seriously, it looked more like the engine oil than it did tranny fluid. Lots of suspended particles, with a gray-black color to it. You couldn't see red unless you smeared it on a white paper towel, and even then it was dark, dirty-red. :eek:

The truck's got 57,700 miles, and I can't figure out what a person would have done with it to make the trans fluid look like that. Even if it was never changed, it should still look something like transmission fluid, shouldn't it? To be doubly-sure what I was looking at, I did both a cold- and warm-check of the fluid color and levels. The levels were right on, and the fluid didn't look quite as bad at the dipstick. However, it was still a real, real dirty red color.

Alright, so now what? Just flushing out the dirty fluid, replacing with new and leaving it for a normal service interval seems like a bad idea, because with that level of contamination in the fluid there'll be a lot of crap still on the various trans parts that'll just badly contaminate the new fluid. So, I'm thinking I'll drain the pan, pull it and replace the internal filter, refill it with el-cheapo (Castrol or Valvoline or whatever) DexIII, and run it for a few hundred miles. I know this won't get all the bad fluid out, but it'll at least let the detergents in the new trans fluid do their job for a little while cleaning out the internal stuff. Maybe I'll do this twice, then replace the internal and external filters again and fill with Transynd or Amsoil? Or would going to get a full system flush, running that for a while, then repeating the process, be a better idea? My only worry about that method would be not replacing the internal filter.

I'm looking for some advice here... :help2:

How many times have you changed your spin on filter? You may not have anything to worry about as I have seen this before and not found anything serious in the Ally after teardown.
mike

This is my first time changing the spin-on in this truck. I bought it from a dealership about a month ago with 56,500 on it. Ran the VIN for service records, but found nothing on trans... Which doesn't really mean anything, I guess. But for all I know, this is the first time the filter has been changed.

On Edit: Sorry, should have made this clear in the first post.

Changing Both filters and the fluid, (removing the pan to change internal filter) would not hurt would it Mike L.. It would sure make me feel better if it was mine.

Idahofox

I woudl do a complete flush using hoots method and keep a close eye on the fluid from there......watching for discolouration and smell.You never did say what the fluid smelled like?

I have seen some really bad looking fluid and did not find much wrong with the trans. I have a feeling that TranSynd discolors badly ( some Allys came with this fluid ) or, the converter going bad can cause discolor also. Most of the really damaged Allys I have worked on had very good looking fluid.

idahofox
You are right on the money.
mike

Fluid had a somewhat burnt odor to it, but not overpowering clutch smell... I dunno, guys, I smoke a pack of cigarettes a day, and I'd been laying under the truck breathing in the 15W-40 and suspension grease for a couple hours before I finally got to the trans filter yesterday, so my sense of smell was less than sharp. The metallic crap suspended in the fluid that came out with the filter was what had me more concerned. After sitting here stewing all day, I think I'll stick with dropping the pan & replacing internal filter for peace of mind, let the filters do their job for a little while, then 'rinse and repeat,' followed by a flush with a full synthetic & a new spin-on. The trans isn't acting strange or anything, so here's hoping the damage hasn't been done yet. Excuse me now while I go hope in one hand and crap in the other to see which of 'em fills up first...

So, I've completed my little maintenance routine... Drained pan, replaced 7 qts. conventional DIII, ran about 300 miles, dropped pan yesterday, replaced sump and spin-on filter -- BTW, thanks to those (Hoot, Mike L, I think) who posted the tips RE the quart of fluid that gushes out when you pull the sump filter, saved me from taking a bath, for sure -- replaced 10 qts. conventional DIII and will run about 1000 miles before I replace with synthetic and change spin-on again. Trans is still operating smooth and normal, although the inside of the pan was covered in a pretty thick layer of metallic film.

But I was in the shower, thinking about how tranny fluid doesn't exactly make your hair 'soft and manageable,' and something else occurred to me: Like I said in the first post, the fluid I drained from it the first time didn't even look like tranny fluid, it wasn't even close to red, in fact, it was purple... As in, ROYAL PURPLE.
:idea: :duh: :shake:

So, yeah, I'm a moron. I dunno, at least I haven't hurt anything (except my friggin' wallet) doing this, and judging from the pan, the fluid probably needed to be changed anyway.

Same situation here. Bought my '03 used from a dealer with 24k on it. Got home and started checking fluids, and my tranny fluid looked the same (black/grey). Freaked and had it in for a full flush and new internal & spin on filters. Flush still doesn't get rid of all the old fluid, so its still slightly dark red now, but now I drain the pan and spin on filter at every oil change until it brightens (better each time). Tranny never acted funny either, and levels were spot on. Hadn't thought about royal purple. My truck was supposed to be a GM truck used to pull Pontiac G6's around to shows and fairs. So it was used hard; now I barely stress it with a 3k lb camper and 3k lb boat. I figure that if it blows up (hopefully never, or at least many years from now), it will give me an excuse to put a really nice tranny so I can BOMB the motor to put out some more power.

I just changed my tranny fluid at 50,000 miles last weekend, previous change was at 20,000 and I used Transynd on that change. Only changed spin on at that time and also at 5000 and 30000, I did not drop the pan. My fluid was not bright red, but was as described above, sort of greyish. My tranny has not been acting funny either. I considered dropping the pan and while I was at it ordering the deeper pan.

All of the fluid does not come out of the pan on drain due to the design of the drain hole (which makes no sense). There has to be some crap in the bottom of the pan, what do you guys think?

Like Mike L said in one of the first posts, he's seen some ugly fluid come out of trannys during teardown with no apparent damage. Maybe there's something inherent about the Ally that causes this, but I don't pretend to know. I just came back from a 1500 mile trip through the mountains, pulling lots of grades (unloaded, but going pretty fast). No strange behavior from the tranny at all, temps never above 200, fluid level spot-on, but still has some dirty-purpleish color to it.

Lightning - I think the drain plug is designed that way (recessed into the pan a little) so you don't catch it on a rock or something off-road and rip it off. I've thought about putting aftermarket drain plug kits on other trucks I've owned, but the prospect of shearing one off, even though unlikely, has kept me from doing it. It's one of those things that would really screw you up if it ever happened -- truck barfing out trans fluid fifty miles past nowhere on some old goat trail of a road. Anyway, yes, you're right, there will be crap in the bottom of the pan. However, even if you got 100% of the fluid out, the metallic film on the inside of the pan would remain. It takes a couple shots with some Brake Kleen to get it off, so the only way to get rid of it is to drop the pan and clean it. I think most guys would tell you it's not worth it. But hey, if you're draining the fluid anyway, it's not much more work to pull the pan off, get that extra quart of fluid, and clean the gunk out. This gives you an opportunity to change the sump filter too (and the quart of fluid that's in it), which is also not really necessary, but good for peace of mind.