72 cj5 axle ratio - Pirate4x4.Com : 4x4 and Off-Road Forum
 
Pirate4x4.Com : 4x4 and Off-Road Forum  

Go Back   Pirate4x4.Com : 4x4 and Off-Road Forum > Brand Specific Tech > Jeep - Non Hardcore
Notices

Reply
 
Share Thread Tools Display Modes
Old 02-20-2006, 07:00 PM   #1 (permalink)
Registered User
 
beat cj's Avatar
 
Join Date: Jan 2006
Member # 64937
Location: York PA
Posts: 77
72 cj5 axle ratio

I have a 72 Cj5 that i have been reassembling for almost a year now. I finally got it running and drove it. It was ungodly high geared. So i jacked up the rear of the jeep and marked the driveshaft to count rotations....My brother turned the wheel a revolution and i counted the shaft rotation. I only came up with about 1.8 turns. This is way low, i never even saw a ring and pinion set this low( numerically). Has anybody heard of a ratio used < 2:1 in the axle?? Any info would help. thanks
beat cj is offline   Reply With Quote
Old 02-20-2006, 07:17 PM   #2 (permalink)
Registered User
 
4x401cj's Avatar
 
Join Date: Oct 2004
Member # 37244
Location: Gresham, Oregon
Posts: 1,020
Pull the rear cover and read the #`s on the ring gear. Most of the `72-`75 cj`s I`ve delt with had 3.73`s. That would be my guess for yours also.
4x401cj is offline   Reply With Quote
Sponsored Links
Old 02-20-2006, 07:31 PM   #3 (permalink)
Registered User
 
beat cj's Avatar
 
Join Date: Jan 2006
Member # 64937
Location: York PA
Posts: 77
yes thats my next step...i am at college and i only get home once in a while so next time i will do that.
beat cj is offline   Reply With Quote
Old 02-21-2006, 06:39 AM   #4 (permalink)
Rock God
 
Haggar's Avatar
 
Join Date: Apr 2002
Member # 11570
Location: Lake Orion, MI
Posts: 2,038
If you only turned one wheel, and the other stayed put, it rotates the driveshaft only 1/2 the number of times.


3.73 gears / 2 = 1.865..

Most of the 72-75 Bastard years had 3.73 gears, some of the 6 cyls had 4.27s. Those were the only gears available.

Both my 75s had 3.73s, one was a 304, one was a 232.
Haggar is offline   Reply With Quote
Old 02-21-2006, 07:56 AM   #5 (permalink)
Granite Guru
 
piratebuggy's Avatar
 
Join Date: Sep 2005
Member # 53597
Location: near St. Louis,MO
Posts: 990
Sometimes it's easier to rotate the wheel 10 times to get a better read on the exact ratio.
__________________
78 Jeep CJ-5 304 ---setting off car alarms with extreme prejudice.......

out cali style!!!!!!
piratebuggy is offline   Reply With Quote
Old 02-21-2006, 12:26 PM   #6 (permalink)
Registered User
 
Join Date: Jan 2005
Member # 40958
Location: Guatemala
Posts: 236
Quote:
Originally Posted by piratebuggy
Sometimes it's easier to rotate the wheel 10 times to get a better read on the exact ratio.
Add 4.10s to that
Chato is offline   Reply With Quote
Old 02-21-2006, 07:11 PM   #7 (permalink)
Registered User
 
Join Date: Feb 2006
Member # 66700
Posts: 26
Haggar, please tell me more about how only turning 1 wheel rotates the drive shaft 1/2 #times. I guess I dont fully understand how differential / drive shaft works. thanks.
pharmvet is offline   Reply With Quote
Old 02-21-2006, 08:55 PM   #8 (permalink)
Registered User
 
beat cj's Avatar
 
Join Date: Jan 2006
Member # 64937
Location: York PA
Posts: 77
hmm your explanation solves the problem 1.8 mystery but I never heard of the driveshaft rotating half as much by only turning one wheel....interesting
beat cj is offline   Reply With Quote
Old 02-21-2006, 09:29 PM   #9 (permalink)
Registered User
 
KiGrind's Avatar
 
Join Date: Feb 2006
Member # 66647
Location: Knoxville, TN
Posts: 1,326
HERE!

http://www.off-road.com/jeep/tech/axle/amc20.html

This page covers all the axels in Jeeps and gives ratios and how to ID them and such.

Helped me!! Turns out I've got an AMC20 3.54 Trak-Lok (Wasn't planningon a locker anyways :-/ not in this weak poo)
__________________
70 Jeepster Commando
95 ZJ
KiGrind is offline   Reply With Quote
Old 02-22-2006, 08:31 AM   #10 (permalink)
Granite Guru
 
piratebuggy's Avatar
 
Join Date: Sep 2005
Member # 53597
Location: near St. Louis,MO
Posts: 990
Of course if you have a limited slip you wouldn't be able to rotate just one wheel.My axle code comes up as a 3.54 Trak-Lok but it can turn one wheel,I was told somebody "went through" the rear axle before I bought it.My question is-to save me having to pull the cover off-is the Trak-Lok a clutch type or torque sensing type of limited slip?(anyone?)The driveshaft only turns half times do to the differential action of the spider gears in an open type diff.
__________________
78 Jeep CJ-5 304 ---setting off car alarms with extreme prejudice.......

out cali style!!!!!!
piratebuggy is offline   Reply With Quote
Old 02-22-2006, 08:48 AM   #11 (permalink)
Registered User
 
KiGrind's Avatar
 
Join Date: Feb 2006
Member # 66647
Location: Knoxville, TN
Posts: 1,326
Quote:
Originally Posted by piratebuggy
Of course if you have a limited slip you wouldn't be able to rotate just one wheel.My axle code comes up as a 3.54 Trak-Lok but it can turn one wheel,I was told somebody "went through" the rear axle before I bought it.My question is-to save me having to pull the cover off-is the Trak-Lok a clutch type or torque sensing type of limited slip?(anyone?)The driveshaft only turns half times do to the differential action of the spider gears in an open type diff.

I think its clutch and mine does the same thing, was told they might need replacing.

I'll do it when I replace the bearings and seals.. What a fun project that will be for me.
__________________
70 Jeepster Commando
95 ZJ
KiGrind is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -7. The time now is 07:10 PM.


Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.0 ©2011, Crawlability, Inc.