Trans fluid needs proper level
Trans fluid needs proper level
So a few years back, I took out my 68 Camaro which has a th400 auto trans. As I turned the corner, it felt like the car had shifted to neutral and back. I went back home and checked the trans fluid level, it was low. I went over to the other garage where it was parked and there was a big spot on the floor. I filled it up and it was fine after that. I have most the leaks fixed but I think my dipstick tube o-ring still seeps some fluid.
What happens is, as I turned the corner, the fluid sloshed over to one side and the filter intake was exposed to air. The same thing would happen as I accelerated kind of hard. The fluid sloshes back and the intake is open to air. The pump loses fluid and thus pressure to apply clutches drops to zero.
Another time, one day at work, a guy who knows I know a bit about cars asked to take his Jeep for a ride. He says, I hear a thunk after I make a turn. I take for a drive and sure enough, after a turn I feel this little thunk. When we get back, I check his fluid, it is low. I tell him he has to add fluid so he says he is going to get some after work and add it. I ask the next day if he got it and did it help? He says he bought it but he checked his dipstick again and it was at the correct level. I said there is a possibility it could be foaming due to sucking air. He sort of ignores me. A couple days later he tells me his Jeep is fixed. I said what was it? He says he added some fluid and now it is okay. I slapped myself in the head and said, "so it was low on fluid! Why didn't I think of that?" He laughed.
You can lead a horse to water...............
What happens is, as I turned the corner, the fluid sloshed over to one side and the filter intake was exposed to air. The same thing would happen as I accelerated kind of hard. The fluid sloshes back and the intake is open to air. The pump loses fluid and thus pressure to apply clutches drops to zero.
Another time, one day at work, a guy who knows I know a bit about cars asked to take his Jeep for a ride. He says, I hear a thunk after I make a turn. I take for a drive and sure enough, after a turn I feel this little thunk. When we get back, I check his fluid, it is low. I tell him he has to add fluid so he says he is going to get some after work and add it. I ask the next day if he got it and did it help? He says he bought it but he checked his dipstick again and it was at the correct level. I said there is a possibility it could be foaming due to sucking air. He sort of ignores me. A couple days later he tells me his Jeep is fixed. I said what was it? He says he added some fluid and now it is okay. I slapped myself in the head and said, "so it was low on fluid! Why didn't I think of that?" He laughed.
You can lead a horse to water...............
- Money pit Beretta
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Re: Trans fluid needs proper level
You tried to lead me. Oh and the GF's car is doing what your 68 was doing. Yes I have a quart here ready to go in. Asked the guy at the tranny shop, this topic is a bit late LOL.
I have never had a problem with low fluid before. Always go by the manual and drain time is like 30min or so. But I did change the fluid/filter on both cars. On mine it was dry and so was the converter. Must have read the manual as an overhaul fill or something.
Oh yeah, the trans shop guy said that there is another way to be sure. Pull the drain plug on the tail shaft(or near CV for us on the passenger side), pour and wait until some comes out.
I have never had a problem with low fluid before. Always go by the manual and drain time is like 30min or so. But I did change the fluid/filter on both cars. On mine it was dry and so was the converter. Must have read the manual as an overhaul fill or something.
Oh yeah, the trans shop guy said that there is another way to be sure. Pull the drain plug on the tail shaft(or near CV for us on the passenger side), pour and wait until some comes out.
Last edited by Money pit Beretta on Thu Dec 25, 2014 9:45 am, edited 1 time in total.
keep'em flying!
- 3X00-Modified
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Re: Trans fluid needs proper level
And depending on what you do with your car you may need to overfill it... I go to the proper fluid level and then add 1qt... If I do not do this my car will not shift at the strip. When it's revving up to 6700 RPM all the fluid is sucked from the pan and spread about the trans.. it cant make it back to the pan quick enough when you only have the proper level so the same deal happens.
Re: Trans fluid needs proper level
Are you feeling better Moneypit?
I've had the flu since last Friday.
Rattling phlegm in my chest is finally going away.
I don't want to be contagious for Xmas day.
I've had the flu since last Friday.
Rattling phlegm in my chest is finally going away.
I don't want to be contagious for Xmas day.
- Money pit Beretta
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Re: Trans fluid needs proper level
I can understand with ease what you said 3X00. Just seems strange after all those years of being told not to overfill. Sometimes teachers just like to scare kids.
Oh man this is a slow roller. Solid head, but nothing running. Got the oil sender and the quart of ATF in the GF's car yesterday. It was like 38F, didn't mind it too much. Paying for it now!
Glad to hear one of us is doing better. Hope you have a good one!
Oh man this is a slow roller. Solid head, but nothing running. Got the oil sender and the quart of ATF in the GF's car yesterday. It was like 38F, didn't mind it too much. Paying for it now!
Glad to hear one of us is doing better. Hope you have a good one!
keep'em flying!
- Asylum
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Re: Trans fluid needs proper level
I had the same issues as Jon with my TH125 and high RPM's.
Ran it at least a half quart overfilled on race days to compensate for the 6600+ RPM shift points.
And I only ever used Type F fluid.
Ran it at least a half quart overfilled on race days to compensate for the 6600+ RPM shift points.
And I only ever used Type F fluid.
Eric
Asylum Motorsports
"Where we're not happy 'til YOU'RE not happy!
'91 California Quad (Gone with just a bit of "Seller's Remorse".)
'92 3500 GT gone and not really missed. It was fun. Documented 13.47 N/A.
Asylum Motorsports
"Where we're not happy 'til YOU'RE not happy!
'91 California Quad (Gone with just a bit of "Seller's Remorse".)
'92 3500 GT gone and not really missed. It was fun. Documented 13.47 N/A.
Re: Trans fluid needs proper level
I think it is fair to say that you are one of the top TH125 experts on this forum... I am fascinated at your use of Type F in it. Would you mind elaborating on the reasoning for this, and is it strictly as a race-purpose application? Did you see accelerated transmission wear from its' use? I am in the works of ditching the TH125 in my Yellow Indy right now, but am potentially interested in a few experiments with the car (not interested in destroying the tranny though -I just can't quite bring myself to ruining good machines even if I personally have no use for them) before tranny-swapping for the five-speed, and might even install the TCC override circuit I designed for it if I get bored enough...Asylum wrote:And I only ever used Type F fluid.
A former co-worker of mine had a base '69 Camaro -307 with the 2-speed Power-Glide trans and experienced similar issues in a different direction. He put on a set of 17" Corvette rims (with custom 2" spacers -it still looked like a giant Match-Box car to me ) and had so much lateral traction from the wide low-profile tires that he would lose fluid-pressure in tight slalom turns. As the engine lost connection to the drivetrain and revved up, he would spin over to the alternate direction turn, the engine would re-engage (at higher RPM) causing the tires to momentarily torque-spin before grabbing, then as the fluid sloshed over to the other side away from the pick-up, he would start it all over again. Last I knew, he was gathering parts up for a LS6/T-56 six-speed swap, and never bothered doing anything with the Power-Glide...
1989 SuperCharged 3800 Srs-II (First)Six-Speed GTU
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26
- Asylum
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Re: Trans fluid needs proper level
Well I am certainly no transmission expert, however one of my best high school buddies just happens to be a fellow racer and happens to own a Mr. Transmission Franchise. (How convenient, eh?)
He liked Type F for my application for a couple of reasons.
It does not have all the friction modifiers found in Dexron, handles heat much better, and resists foaming under load and high RPM.
Couple of things though.
Once a trans has had exposure to Dexron you cannot switch to Type F.
Secondly, it is not a recommended application for "daily" driving. My car was mainly highway/race/highway and saw very little city usage, however I never had any issues.
It also had a 3:73 FDR so was always up in the RPM range regardless of where it went.
And let's not underestimate the fact this trans was out of the car about every 6 or 8 weeks for a "freshening". (Free maintenance is still free, other than a few Molson and some wings.)
However it never broke, slipped or caused me any concern whatsoever, was still the hardest shifting FWD car I have ever been in and 1.87 60' times don't lie.
Would I recommend it for a Daily Driver. NO!
BTW the TCC is programmable and can be adjusted or eliminated during the tuning process.. Or you can just unplug it.
He liked Type F for my application for a couple of reasons.
It does not have all the friction modifiers found in Dexron, handles heat much better, and resists foaming under load and high RPM.
Couple of things though.
Once a trans has had exposure to Dexron you cannot switch to Type F.
Secondly, it is not a recommended application for "daily" driving. My car was mainly highway/race/highway and saw very little city usage, however I never had any issues.
It also had a 3:73 FDR so was always up in the RPM range regardless of where it went.
And let's not underestimate the fact this trans was out of the car about every 6 or 8 weeks for a "freshening". (Free maintenance is still free, other than a few Molson and some wings.)
However it never broke, slipped or caused me any concern whatsoever, was still the hardest shifting FWD car I have ever been in and 1.87 60' times don't lie.
Would I recommend it for a Daily Driver. NO!
BTW the TCC is programmable and can be adjusted or eliminated during the tuning process.. Or you can just unplug it.
Eric
Asylum Motorsports
"Where we're not happy 'til YOU'RE not happy!
'91 California Quad (Gone with just a bit of "Seller's Remorse".)
'92 3500 GT gone and not really missed. It was fun. Documented 13.47 N/A.
Asylum Motorsports
"Where we're not happy 'til YOU'RE not happy!
'91 California Quad (Gone with just a bit of "Seller's Remorse".)
'92 3500 GT gone and not really missed. It was fun. Documented 13.47 N/A.