Transmission Tutorial
Steve Ochs
Procedure
The 4T60-E is a FWD transmission. You are right about it being transverse and it is the original THM-440T4 except it has electronic controls. The 4L60 is the 700-R4 which is a 350 with an Overdrive. The 4L60-E is an electronic shift version. The 4L80 is an overdrive version of the 3L80 (the old 400). The 4L80-E is an electronic shift version. Below is the contents of a message I posted to the Oldsmobile list. It describes characteristics of each of GM's later transmissions.

Someone asked the question about the 4T60/65-E replacing the 700-R4. The 700-R4 is now known as the 4L60-E. The 4T60-E is a FWD tranny. The 4T65-E is new this year for the hi-po applications (Grand Prix GTP, Riviera S/C, Monte Carlo Z-34, etc). Unfortunately this will not help the racers out.

The 4L60-E (700-R4) was improved again this year. Shift quality and durability was enhanced. But the real choice for heavy duty racing is the 4L80-E or the 400. Here are some comparisons of ratings:

If you note, the engine torque rating for the 200-4R and the 700-R4 is very close in stock form. Considering the weight advantage, the gear ratio preference, deeper overdrive, and the fact that the 700-R4 only comes in Chevy bolt pattern, the 200-4R is preferable for most street applications when built properly.

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Transmission
Model		 Weight
(Lbs)		 Engine
Torque
(lb/ft)		 Gearbox
Torque
(lb/ft)		 Gross
Veh. Wt.
(lbs)		 Torque
Conv. Dia.
(inches)		 Overall
Length
(inches)
Rear Wheel Drive:
THM 180C (3L30) 130/140 258 440 7716 9.6/10.24 26.29/28.11
4L30-E 168/177 258 440 7716 9.6/10.24 28.54/31.57
THM 200-4R 157 330 550 6000 11.73 28.26
THM 700-R4 (4L60) 167/184 350 650 8600 9.6/11.73 29.77/30.64
4L60-E 160/176 350 612 8600 9.6/11.73 29.77/30.64
THM-400 (3L80) 190 440 885 12000 12.20 29.30/34.48
4L80-E 260 440 885 15000 12.20 31.93/33.02
Front Wheel Drive:
THM 125C (3T40) 161 200 416 5100 9.64
THM 440-T4 (4T60) 195 235 369 5181 9.64
4T60-E 203 280 390 6400 9.64
4T65-E 214 285 400 6400 9.64/10.16
4T80-E 295 305 461 6800 10.43

Gear Ratio Chart:

Transmission
Model		 First Second Third Fourth Reverse
Rear Wheel Drive:
THM 180C (3L30) 2.400 1.479 1.000 ----- 2.000
4L30-E 2.400 1.479 1.000 0.723 2.000
4L30-E Optional 2.860 1.620 1.000 0.723 2.000
THM 200-4R 2.741 1.568 1.000 0.674 2.067
THM 700-R4 (4L60) 3.059 1.625 1.000 0.696 2.294
4L60-E 3.059 1.625 1.000 0.696 2.294
THM 400 (3L80) 2.482 1.482 1.000 ----- 2.077
4L80-E 2.482 1.482 1.000 0.750 2.077
Front Wheel Drive:
THM 125C (3T40) 2.840 1.600 1.000 ----- 2.067
THM 440-T4 (4T60) 2.921 1.568 1.000 0.705 2.385
4T60-E 2.921 1.568 1.000 0.705 2.385
4T65-E 2.921 1.568 1.000 0.705 2.385
4T80-E 2.960 1.626 1.000 0.681 2.130


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