| Author |
Message |
C. Ray Powell (Raypowell)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, April 26, 2005 - 10:40 pm: | |
I have MCI 5C with 6V71 and MT644 tranny.
Don't do so well in the hills. In upshifting from 3rd to 4th rpm's drop 500 rpm's. I'm thinking if I had another gear I wouldn't lose so many rpm's. How about using a MT653? What do you think?
Thanks
C Ray |
DMDave
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, April 26, 2005 - 11:58 pm: | |
Ray do you know what your final drive ratio is? Just wondering. How do you like the coach other wise, fuel economy etc. Good luck |
Henry R. Bergman, Jr. (Henryofcj)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, April 27, 2005 - 5:19 pm: | |
I am not sure if the 653 close ratio 5-speed would help you that much. Your 4-speed has around... a 3.58 1st, around a 2.04 2nd, around a 1.37 or 1.38 3rd and a direct 4th or high gear. My memory is suspect here, some help from others would be greatly appreciated.
The CLOSE RATIO 653 or type has around...duh, duh, a 4.14 or sooss 1st, a 2.28 or soooss 2nd, a 1.68 or soosss 3rd (guessing here) and around a 1.28 or soooss to one 4th. Fifth is direct one to one.
With your application, your would have a choice of a 1.37 or 1.38 to one or (with the five speed) around a 1.28 to one. Not that much difference to help that much, except under ideal conditions. of grade, elevation and temperature.
Plus, and I'm not sure here, you MAY not have enough drive shaft length to properly handle the longer 5 speed Allision. U-joint anglarity and service life become a concern. Others may provide more exact info. Sorry and good luck. |
T. (Bluegrass)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, April 27, 2005 - 10:01 pm: | |
Net input power (max).............................250 hp (186 kW)
Input speed range................................2000 - 4000 rpm
Net input torque (max)........................640 lb ft (868 N·m)
Vehicle weight (GVW or GCW)..........Up to 73,280 lbs (33,239 kg)
Direct..............SAE 2 flywheel housing with flex plate drive
Type.........................Single-stage, 3-element, multiphase
Stall torque ratio.........TC 350-3.04; TC 360-2.86; TC 370-2.40;
TC 378-2.27; TC 380-1.82
Lockup Clutch, automatic..................Effective in 3rd & 4th First...................................3.58:1 Second..................................2.09:1 Third...................................1.39:1 Fourth..................................1.00:1 Reverse.................................5.67:1 * Gear ratio does not include torque converter
Length..........................................30.4 in (773 mm)
Width...........................................19.3 in (489 mm)
Height (with 5.1" pan).........................22.4 in (568 mm)
Weight (dry)....................................510 lbs (231 kg)
Weight (dry) w/output retarder..................638 lbs (289 kg)
Net input power ..................................250 hp (186 kW)
Input speed range................................2000 - 4000 rpm
Net input torque (max)........................640 lb ft (868 N·m)
Vehicle weight (GVW or GCW)..........Up to 73,280 lbs (33,239 kg) Direct..............SAE 2 flywheel housing with flex plate drive Type..........................Single-stage, 3-element multiphase
Stall torque ratio.........TC 350-3.04; TC 360-2.86; TC 370-2.40;
TC 378-2.27; TC 380-1.82
Lockup clutch, automatic..................Effective in 4th & 5th Here Is the MT653 First...(manually selected).............8.05:1
Second..................................3.58:1
Third...................................2.09:1
Fourth..................................1.39:1
Fifth...................................1.00:1
Reverse.................................5.67:1
* Location............................Right side (viewed from rear)
Drive gear ratio............... All ranges--1.00 x turbine speed
Drive gear rating.................300 lb ft (407 N·m) continuous Oil type........................................Dexron III®, C 4
Capacity (excluding external circuit).....18 U.S. qts (17 liters)
(w/std. oil pan)
Filter............Full flow, replaceable element, remote mounted
Cooler............................................Remote mounted
(Filter and Cooler not furnished on transmission assembly but is supplied
by vehicle manufacturer.) Length..........................................36.2 in (920 mm)
Width...........................................19.3 in (489 mm)
Height (with 5.1" pan).........................22.4 in (568 mm)
Weight (dry)....................................602 lbs (273 kg) |
C. Ray Powell (Raypowell)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, April 27, 2005 - 10:35 pm: | |
Dave, the final drive is 3:33. Also kicking around the 6V92 deal. Just trying to find a CHEAP way to get up the hills better. We still really like the coach. Handles well, looks good!
C Ray
Bluegrass, where did you get all the info. I looked on Allison site , but could not find the info.
C Ray |
T. (Bluegrass)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, April 27, 2005 - 11:00 pm: | |
I have most of the Info on the Allison Transmission In a file and have had them for about 4 years now I got them before allison started charging for them. |
mci102
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, May 01, 2005 - 12:55 am: | |
I also have a MC5C with a 671 except with a 740. The probem is lack of power as you likely know and more gears won't really help much. I have seen both the 6V92 and the 8v-71 installed with a MT 644. The series 50 I think would also fit and work well, but have never seen one installed. |
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