Converter Slippage by gear?
06-14-2005, 08:32 AM
#3
I believe so, as I have seen. The reason is due to the greater leverage in the lower gears. The engine can easily over power the output side, since the car is not moving and has built up less moving inertia. The faster you go, the easier it becomes for the trans (or converter) to keep up. 
06-14-2005, 08:34 AM
#4
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3rd has the most slippage then 2nd and 1st. Why? Because you loose the advantage of gear torque multiplication that you have in 1st and 2nd gear and that equates to more load on the TC.
John
John
06-14-2005, 09:03 AM
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Originally Posted by JNorris
3rd has the most slippage then 2nd and 1st. Why? Because you loose the advantage of gear torque multiplication that you have in 1st and 2nd gear and that equates to more load on the TC.
John
John
06-14-2005, 10:34 AM
#6
Originally Posted by JNorris
3rd has the most slippage then 2nd and 1st. Why? Because you loose the advantage of gear torque multiplication that you have in 1st and 2nd gear and that equates to more load on the TC.
John
John
I recently bought a TH350 and paid extra for the 2.75 first gear. Well, I was worried I accidentally got the 2.52 first gear because at 6800 RPM in 1st gear I was going 47 mph. That seemed awfully high to me. I have 4.10 rear gears and 27" slicks. I found a gear/mph calculator that does not take into account slippage. If I enter 2.75 it says I should be going 48.5 mph @ 6800 RPM but if I enter 2.52 it says I should be going 51 mph.
47/48.5= .9691 (About 3% slippage) if 2.75 first gear
47/51.0= .9216 (About 8% slippage) if 2.52 first gear
According to my converter's manufacturer, my converter should have about 5% slippage. So as you can see, I was stuck in the middle and didn't know which 1st gear ratio my TH350 has.
I do know my second and third gear ratios. At 6500 rpm in 2nd gear I was going 79 mph but the calculator said I should be going 85. At 6400 rpm in 3rd gear I was going 118 mph but the calculator said I should be going 128.
79/85 = .9294 (About 7% slippage) for 2nd gear
118/128 = .9219 (About 8% slippage) for 3rd gear
So it looks like 3rd gear has 8% slippage, 2nd gear has 7% slippage and 1st gear has 3% slippage. Does this sound right? If not, maybe I did get a 2.52 first gear by mistake.
06-14-2005, 12:20 PM
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Originally Posted by PewterZ28
So it looks like 3rd gear has 8% slippage, 2nd gear has 7% slippage and 1st gear has 3% slippage. Does this sound right? If not, maybe I did get a 2.52 first gear by mistake.
