Re: Change dark ATF ?

OK, next time he buys a used car, he's taking it to a mechanic or calling the auto club for a $25-50 once-over before plunking down his money, right? Even if you have mechanical skills this is a good idea. You're paying as much for objectivity as for expertise; by the time you've gotten that far it's implicit that you want the vehicle. This is definitely something they'd have brought to his attention.

Anyway.

Dark, burnt-smelling transmission fluid is a symptom of transmission overheating. It is not necessarily a symptom of trouble, but I'd consider it an indication that trouble should be watched for in other ways. Whether this is a symptom of overenthusiastic trailer-towing or a lot of wheelspin after getting stuck or just a car that runs a bit hotter than usual and needs regular changes or something else that I haven't thought of, I dunno.

I'd change the transmission fluid and filter (or have this done by a local shop that I trusted not to reflexively try and sell me a new tranny). This is also a good opportunity to perform any routine adjustments that the shop manual might indicate -- I'm not deeply familiar with this make, model, and year. Then I'd monitor its operation and the color of the fluid for the next few months.

That's a sign that the transmission survived its ordeal, and at best is okay and at worst is worth fixing. Discolored, smelly fluid is an initial sign of something wrong; funny noises and weird shifting can indicate more advanced problems, so if you have the former but not the latter, good good good.

Some say that; others say that continuing to run oxidized (discolored and burnt smelling) and perhaps particulate contaminated transmission fluid will over time damage a transmission that survived the first bit of abuse.

I personally would change the fluid and, if applicable, filter, given these symptoms. If there were indications of varnish buildup, I'd change it again in a couple of months, in case the detergent properties of the first round of new fluid have cleaned out something I'd rather not have in there.

There are also companies that will analyze transmission fluid just as they do motor oil; you might use that as an indication of whether the second change is needed. You can find them with a Web search.

Best of luck,

--Joe

This is definitely not true, as the fluid continues to degrade and oxidize, it will cause more harm than good. Mechanics sometimes say the fluid is what's holding the transmission together, they do that to sell transmissions. They tell you to keep driving it until it fails, and guess what? It will! If your fluid contains enough metal or friction material to be "holding the transmission together" then the car is more often than not exhibiting serious transmission shifting and engagement issues and you wouldn't be telling us...

Then there is the debate over changing just the fluid in the pan and swapping in a new filter, or flushing the whole system. I won't get into that. But it might not be a bad idea to flush if that is original ten year old 90K mile dark Toyota ATF.

Correct me if I'm wrong, but don't some imports like Honda and Toyota use a different transmission fluid that *is* a darker red?

Alan Moore Dallas, TX

Notice - I do not respond to the above email address, change the ilema to crownvic to respond to this message outside of this thread.

"Philip®" wrote

No, I read him right. And if I'm reading you right, you are saying that FWD vehicles do not use hypoid ring pinion gears. This is incorrect. Audi uses hypoid ring/pinion gears, some Chryler cars use hypoid, the old Renaults that were "Eagles" used hypoid.

Yeah, I think that was my point.

Ian

In news:BTqdc.56095$Ig.41585@pd7tw2no, shiden_Kai being of bellicose mind posted:

Ian.... you interpreted Tegger's post while I read it as written. You are also reading into my post something that isn't there.

along the same lines, can anyone edjumacate me as to what exactly "Klingelnberg" gears are? was reading through the shop manual for my

944 (hey, it's more educational than Hustler and your girlfriend won't bitch at you when she finds the shop manual in the can) and saw this term referring to the final drive gears. They appear to be some sort of cross between hypoid and bevel gears looking at the pictures. They are also noisy, although I don't know if that's by design or through wear :(

nate

"Philip®" wrote

Ok, let's go back to the beginning. Here is the original post of Tegger's that I responded to.

Here's what I read: the poster that he is responding to said, "my trans guy put hypoid oil in my 'final drive'" Tegger responds: "I thought that stuff (hypoid oil) was only for hypoid diffs as used in Rear Wheel Drive cars". To which I replied: "You thought wrong". Which, as far as I can tell, is correct, as hypoid oil is used in "Front Wheel Drive" cars too. With me so far?

Next, I read this: "The diff in a Front Wheel Drive car does not have hypoid gearing (and doesn't need to). To which I respond:

I think this all makes perfect sense, but feel free to tell me where I misinterpreted what he was saying.

Ian

Technically they are epicyclical spiral bevel gears using Klingelnberg?s Cyclo-Palloid System. See:

In news: snipped-for-privacy@posting.google.com, Nate Nagel being of bellicose mind posted:

Klingelnberg (the proper name for palloid spiral cut bevel gears) are known generically in the automobile/truck arena as hypoid gears.

In news:_qBdc.60133$Ig.57778@pd7tw2no, shiden_Kai being of bellicose mind posted:

The CONTEXT. The context IS a 1992 Toyota Corolla ... a front wheel drive car without hypoid final drive gears. :-)

"Philip®" wrote

That's not what Tegger said. He was shotgunning "all" FWD vehicles.

Ian

MY '92 Corolla does have planetary gears....acording to the official Toyota repair manual...

Scott in Florida

In news:JnCdc.57374$Pk3.56157@pd7tw1no, shiden_Kai being of bellicose mind posted:

Tegger was commenting about Scott's original post concerning his (Scott's) 1992 Corolla with the 3 speed automatic.

In news: snipped-for-privacy@4ax.com, Scott in Florida > > > written. You are also reading into my post something that

Your A131L automatic does have helical cut gear sets in its planetary. This provides two forward reductions (1st, 2nd), and Reverse (also a reduction). They are lubricated with ATF, which is shared with the valve body, clutches, and band. It does not have a planetary final drive.

"Philip®" wrote

Very true, and >The diff in a FWD car does not have hypoid gearing (and doesn't need to).

Note the words "a FWD car".....not "1992 Corolla"? As usual on these newsgroups, sweeping statements made by folks who may not be completely up to speed on the topic they are commenting on.

Ian

In news:b6Idc.62377$Ig.42902@pd7tw2no, shiden_Kai being of bellicose mind posted:

People "in the know" such as Tegger ... don't have to innumerate all the "it has this ... it does not have that" for your edification.

Again, CONTEXT.

I'll let you have the last word because that's what will put an end to this inane thread so far as I am concerned.

"Philip®" wrote

Good excuse, Philip.

Even your buddy Tegger admits in a previous post that he learned something by doing a little bit of searching around. He managed to find out that Dodge Intrepids use a transaxle with hypoid final drive gears. So why you are going to all the trouble to defend him is beyond me. Something to do with the little symbol after your names?

Anyway, I give him full marks for doing some investigating and finding out that he can always learn something new.

You, on the other hand, are pathetic for attempting to salvage a losing argument on behalf of someone who doesn't appear to even hold your view.

Ian

I have 250k km and have never changed the ATF which is clear and red. I called two transmission shops and both advised me NOT to change the ATF as problems could likely develop. There are many threads on this subject, both pro and con. Do a google group search. IMO, 90k is not too long for a change

There is no specified change interval for the Corolla (97) ATF unless operated in 'severe conditions' according to the maintenance schedule on toyota.com

"Philip®" spake unto the masses in news:MzKdc.4019$A snipped-for-privacy@newsread1.news.pas.earthlink.net:

Well, actually, I was NOT aware that some FWD cars have hypoid gears. My statement WAS a blanket one, and an erroneous one, as it turns out.

"Tegger®" wrote

Hey, we all have lots to learn about all sorts of different things. Philip was probably responding more to my snarky attitude (grin)....my apologies.

Browsed your web site....good to see people putting up useful info for other folks.

Ian