Help! Smoked 4L70E Post-mortem Analysis (W/pics)
10-09-2017, 07:08 PM
#21
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A harsh 2nd won't cause that, But will cause accelerated spline wear on several components.
10-09-2017, 08:39 PM
#22
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I'm not referring to the clutch release "helper" springs around the 3-4 clutch.....Those do get removed when running a HD2 shift kit or 7-CS spring kit. I'm talking about the damper springs in the TCC piston inside the torque converter. "Most" billet TCC pistons lack damper springs which is OK if you don't let any harmful harmonics through the unit.....A bad misfire can contribute.
A harsh 2nd won't cause that, But will cause accelerated spline wear on several components.
A harsh 2nd won't cause that, But will cause accelerated spline wear on several components.
Thanks for the info!
The splines actually look like the only thing left in the trans without wear on it lol.
After doing some reading, it seems pretty common to remove the 3-4 "helper" return springs from the drum. Should i follow??
The converter is a TCI super street fighter.. Not sure if that means anything. I dont think it has billet components?
as a reminder, this truck is a DD for the most part. I dont hit the strip, but i do pound on it on the weekends.
Last edited by jthomas; 10-09-2017 at 09:12 PM.
10-09-2017, 08:59 PM
#23
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My new 3-4 pack is (9) .065" GPZ frictions, and (9) .060" steels...
I currently have the stock .192" pressure plate, a .214" 5 tang (HD) apply plate, and a .092" snap ring. I cant fit the snap ring in the drum groove (lack of clearance).
What size pressure/apply plates/ snap ring do i need to accommodate the clutches with appropriate clearance??
AND HOW DID I MANAGE TO ONLY DESTROY ONE FRICTION AND TURN ALL THE STEELS BLUE?
My new 3-4 pack is (9) .065" GPZ frictions, and (9) .060" steels...
I currently have the stock .192" pressure plate, a .214" 5 tang (HD) apply plate, and a .092" snap ring. I cant fit the snap ring in the drum groove (lack of clearance).
What size pressure/apply plates/ snap ring do i need to accommodate the clutches with appropriate clearance??
AND HOW DID I MANAGE TO ONLY DESTROY ONE FRICTION AND TURN ALL THE STEELS BLUE?
Last edited by jthomas; 10-09-2017 at 09:14 PM.
10-09-2017, 10:05 PM
#25
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My new 3-4 pack is (9) .065" GPZ frictions, and (9) .060" steels...
I currently have the stock .192" pressure plate, a .214" 5 tang (HD) apply plate, and a .092" snap ring. I cant fit the snap ring in the drum groove (lack of clearance).
What size pressure/apply plates/ snap ring do i need to accommodate the clutches with appropriate clearance??
AND HOW DID I MANAGE TO ONLY DESTROY ONE FRICTION AND TURN ALL THE STEELS BLUE?
My new 3-4 pack is (9) .065" GPZ frictions, and (9) .060" steels...
I currently have the stock .192" pressure plate, a .214" 5 tang (HD) apply plate, and a .092" snap ring. I cant fit the snap ring in the drum groove (lack of clearance).
What size pressure/apply plates/ snap ring do i need to accommodate the clutches with appropriate clearance??
AND HOW DID I MANAGE TO ONLY DESTROY ONE FRICTION AND TURN ALL THE STEELS BLUE?
A 9 friction set-up normally requires a aftermarket backing/pressure plate &/or a thin snap ring.
10-12-2017, 08:58 PM
#27
When lockup happened early and your in 3-4 gears low speeds you can get a almost trailer hitch effect basically the steel in the set rattle back and forth in the drum leaving marks , They are not a huge deal unless really bad but usually if they can easily be cleaner up with a rolock disk or file its not an issue , You might try raising lockup to a higher speed many go with over 40mph in 4th gear only
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10-13-2017, 08:43 PM
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When lockup happened early and your in 3-4 gears low speeds you can get a almost trailer hitch effect basically the steel in the set rattle back and forth in the drum leaving marks , They are not a huge deal unless really bad but usually if they can easily be cleaner up with a rolock disk or file its not an issue , You might try raising lockup to a higher speed many go with over 40mph in 4th gear only
but i also increased my lockup pressure, so instead of it sliding in, it felt like another shift.
I guess i still dont understand why its bad to engage at low speeds. now i understand what happens, but i still dont understand why that should happen.
10-17-2017, 03:29 PM
#29
The lockup setting were stock, but i did then end up making it lockup sooner because of the increase stall. (i didnt like cruising around 3k+ rpm)
but i also increased my lockup pressure, so instead of it sliding in, it felt like another shift.
I guess i still dont understand why its bad to engage at low speeds. now i understand what happens, but i still dont understand why that should happen.
but i also increased my lockup pressure, so instead of it sliding in, it felt like another shift.
I guess i still dont understand why its bad to engage at low speeds. now i understand what happens, but i still dont understand why that should happen.
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