?who down shifts Automatics
Both my A4 and the M6, I use 3rd gear when going down a steep hill, while pumping the brakes as needed. I think the only time I'd use a gear lower than 3rd would be if I lost my brakes and had to rely on the transmission and the hand brake to stop me.
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From: troy NH
like you said .camaro 69 coasting down hill about 30 mph one spot i .tryed it in one spot to 2 gear ,not regular .like a manual .thanks guys yes i would . rather do shoes then a tranny,in the th350 its awsome to shift down to gear 2 an hear the roar at about .80 mph but that has shift kit tranny cool an so on ,but one can also go pretty fast in gear 2 with th350
Last edited by 95 camaro 406; Aug 27, 2015 at 10:54 AM.
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I've heard its bad for the trans also - can anyone verify this?
I generally leave it in OD and use my right foot to change gear.
If i'm spirited driving around hills or something, i'll shift it to D so it doesnt constantly shift gears as often.
I'll very rarely go any lower then D. Normally only if i'm going up a hill slowly and dont want it shifting gears, but I reckon the LT1 has enough torque that its not really an issue
Replacing brakes is cheaper then replacing a transmission
I generally leave it in OD and use my right foot to change gear.
If i'm spirited driving around hills or something, i'll shift it to D so it doesnt constantly shift gears as often.
I'll very rarely go any lower then D. Normally only if i'm going up a hill slowly and dont want it shifting gears, but I reckon the LT1 has enough torque that its not really an issue
Replacing brakes is cheaper then replacing a transmission
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I was thinking about this more and it got me wondering. Wouldn't using the lower gears, at least to help you stop, be harder on the differential? I feel like it would be putting more stress on the gears, I could be wrong.
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As mentioned before down shifting can cause heat, "heat kills transmissions". That was a sign at the front of my transmission class
If your normal cooling system is working properly and you are not pushing the car hard then down shifting is not a big deal. Since the transmission has a cooling system and brakes do not down shifting is recommending on long downgrades.
BUT
You really need to think about what you are doing. Normally when your engine is running the piston is pushing the connecting rod against the crank but when you down shift you are using the vacuum in the engine to slow the crank, This is the reverse pressure meaning the crank is pulling on the rod cap. If you screw up and pull in to low a gear and through all the weight of the car against the crank it will stretch the rod and spin a rod bearing.
I witness this once from the passengers seat when a guy with a stick put car in second to down shift going almost 50 MPH with the engine at lower RPMs. I also have had several customs with spun bearing admit that the damage occurred right after a down shift.
As a general rule I down shift sticks and I have taught myself to push the clutch in during emergency situation. I do not down shift my automatic. I just stick it on OD and drive. Oh and first generation overdrive transmission has issues with OD but unless you are driving something with the original trans from 1984 you are fine just leaving the car in OD.
If your normal cooling system is working properly and you are not pushing the car hard then down shifting is not a big deal. Since the transmission has a cooling system and brakes do not down shifting is recommending on long downgrades.
BUT
You really need to think about what you are doing. Normally when your engine is running the piston is pushing the connecting rod against the crank but when you down shift you are using the vacuum in the engine to slow the crank, This is the reverse pressure meaning the crank is pulling on the rod cap. If you screw up and pull in to low a gear and through all the weight of the car against the crank it will stretch the rod and spin a rod bearing.
I witness this once from the passengers seat when a guy with a stick put car in second to down shift going almost 50 MPH with the engine at lower RPMs. I also have had several customs with spun bearing admit that the damage occurred right after a down shift.
As a general rule I down shift sticks and I have taught myself to push the clutch in during emergency situation. I do not down shift my automatic. I just stick it on OD and drive. Oh and first generation overdrive transmission has issues with OD but unless you are driving something with the original trans from 1984 you are fine just leaving the car in OD.
Last edited by Gorn; Sep 5, 2015 at 11:06 AM.
From what I've read a lot of modern cars any more will cut fuel and retard the timing when the computer sees the rpms raise but the speed decrease to help spare the engine from any major damage during engine braking.
However, I still wouldn't try downshifting from OD to 1st at even 25 mph let alone 50. When I downshift in the M6 I try my best to match the rev so you never really notice I actually downshifted.
However, I still wouldn't try downshifting from OD to 1st at even 25 mph let alone 50. When I downshift in the M6 I try my best to match the rev so you never really notice I actually downshifted.
