Transmission A/T Temp Warning Suggestions (1 Viewer)

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I just did my front end rebuild and Brakes overhaul. Took the car out and spent some time doing "slowdowns" to bed in the brakes and rotors.

On the way home(short distance overall) I heard something sounding like "increased car noise". Like increased wind noise. Very diffuse nebulous noise. This was at about 35-40 mph. I put the transmission in neutral and coasted and the noise stayed the same. Went down with decreased speed. Put back into D and drove the 2 miles home or so.

When I pulled into the garage. I saw a check engine light and A/T Temp light. The CEL didn't scare me so much but the A/T Temp light did. I left the car running and noticed a rattle under the car in the area of the transmission. This kinda sounded like the heat shield rattling, but I usually only hear that when accelerating when cold.

I shifted back and forth from Neutral to drive and am getting clunking, that I was hoping to resolve with new Flanges and diff mounts. The flanges have been done the mounts have not.

Checked the CEL and it was O2 sensor complaint. By that time the A/T temp had gone off. The engine had been shut down.

My worries are the transmission. It was not doing anything untoward when driving and I was working it some with the accelerations and slow downs.

I just got a better OBD2 checker so that I can do a check on Trans temps, etc.

Here's where I am at so far.

1) Drained the Trans Fluid. Got a little over a gallon out. DARK red. While it was draining the stream was pretty clear. But looking at it in a shot glass or the pan, not so clear, very DARK. Pulled a Neodynium magnet through it and got nothing. I am going to strain it through some cheescloth and look closer. I believe this "may" be original 2002 Fluid with 220K on it. Maybe changed once, but I don't think so. :oops:

2) Put drain plug back, nothing else so far.

What would you do at this point? If the trans tamp comes up, will it turn on the Aux fan? Maybe that's what I heard? Although I didn't hear that when I stopped in the garage.
Maybe my reverse to drive clunk is transmission? I assumed Flanges, Mounts, or Driveshaft Lube needed.

The A/T Temp Light has me spooked, didn't know it even existed. Should I refill with clean fluid and drive or do any other test/analysis? I'm scared...
 

JunkCrzr89

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Drained the Trans Fluid. Got a little over a gallon out. DARK red. While it was draining the stream was pretty clear. But looking at it in a shot glass or the pan, not so clear, very DARK. Pulled a Neodynium magnet through it and got nothing. I am going to strain it through some cheescloth and look closer. I believe this "may" be original 2002 Fluid with 220K on it. Maybe changed once, but I don't think so.
I suggest proceeding forward after the fluid exchange to see if the rattle/noise persists or the A/T light comes back on. If so, then stop and reevaluate.

Was the fluid that you drained out completely oily like ATF or did it have a slightly watery texture? I ask because the cooler in the bottom of the radiator can fail and allow ATF and coolant to mix, causing AT problems, but with red ATF and red coolant, you may not visually notice such mixture immediately (especially if caught early before it turns to strawberry milkshake). So I will ask the age old question, how old is your radiator? Also, probably worth checking the AT hoses to the radiator, the external ATF cooler in front of the radiator, and the hoses going from cooler back to AT for leaks. Low ATF level (from leak in AT cooling system), overfilled AT cooling system (from coolant leaking into AT system), and overheating of AT (among other things) are common causes of an AT light coming on for most vehicles.

Also, I agree with @ramangain about AT cooling with speed in SFL via airflow. Perhaps while going through the speed up-slow down process of bedding the brakes you were inherently driving too slow to keep the AT temp low while the AT was working pretty hard to repetitively upshift and downshift in rapid succession.
 
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My 4 speed is funny too. It seems to hold 140-160 no matter if it's 40 outside or 110, BUT, driving on a certain street, I see it jump to 180-190, when I make a right to the street I want to be on it goes back down fast. I don't really notice that happening on any other streets. Maybe it's just a weird uphill incline/scenario (not steep enough to downshift)? My fluid is fresh and fluid level is proper following the FSM. My radiator and atf cooler fins are clean too.
 
Joined
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South Florida
I suggest proceeding forward after the fluid exchange to see if the rattle/noise persists or the A/T light comes back on. If so, then stop and reevaluate.

Was the fluid that you drained out completely oily like ATF or did it have a slightly watery texture? I ask because the cooler in the bottom of the radiator can fail and allow ATF and coolant to mix, causing AT problems, but with red ATF and red coolant, you may not visually notice such mixture immediately (especially if caught early before it turns to strawberry milkshake). So I will ask the age old question, how old is your radiator? Also, probably worth checking the AT hoses to the radiator, the external ATF cooler in front of the radiator, and the hoses going from cooler back to AT for leaks. Low ATF level (from leak in AT cooling system), overfilled AT cooling system (from coolant leaking into AT system), and overheating of AT (among other things) are common causes of an AT light coming on for most vehicles.

Also, I agree with @ramangain about AT cooling with speed in SFL via airflow. Perhaps while going through the speed up-slow down process of bedding the brakes you were inherently driving too slow to keep the AT temp low while the AT was working pretty hard to repetitively upshift and downshift in rapid succession.

It was oily like ATF. I just strained it through cheescloth and it was clear. Nothing on the cheescloth. No leaks, no changing ATF levels. ATF level is fine, not low or high. My coolant is grean. There did not seem to be any water in the ATF. Radiator is Originale.

I was accelerating to 45 and standing on the brakes and doing it again and again whiles driving around in circles for a bit. Didn't think it was enough to cause issues. The ATF is worn out though I'm pretty sure.
 

ramangain

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It's not a PITA for the 4spd. We have a dipstick tube to fill from up top.

Drain, reinstall plug and washer, disconnect tranny oil cooler return line, connect exterior hose, replace fluid drained from pan, run truck to collect fluid 3Q at a time, refill after 3Q (do this three times), disconnect exterior hose, reconnect OEM hose, check level, drive a bit, then recheck level, done.

Took me two hours tops from jack up to tires down, and I'm old, slow, and kinda fat.
 
Joined
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It's not a PITA for the 4spd. We have a dipstick tube to fill from up top.

Drain, reinstall plug and washer, disconnect tranny oil cooler return line, connect exterior hose, replace fluid drained from pan, run truck to collect fluid 3Q at a time, refill after 3Q (do this three times), disconnect exterior hose, reconnect OEM hose, check level, drive a bit, then recheck level, done.

Took me two hours tops from jack up to tires down, and I'm old, slow, and kinda fat.

Just found that thread, I'll re-read it, thanx!
 
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Flushing transmission when you've a transmission dipstick, is a walk in the park. Just take your time and keep ahead of fluid coming out. You do not want to run the pan dry of ATF.
 

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