Detroit Locker not engaging - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep CJ Forum > Detroit Locker not engaging

Smittybilt Hard Tops @ Oconee Off-Road! 706-534-9955XHD Heavy-Duty Hood Latches for JK and TJ available at OcoFS: Jeep Fog Light LED Bulbs! Several Brightness Options!

Reply
Unread 04-17-2014, 04:37 AM   #1
79CJGA
Registered User
 
Join Date: Apr 2014
Location: Duluth, GA
Posts: 2
Detroit Locker not engaging

Hi All,, My first post here.
I have a Dana 44 rear with a Detroit locker in it. It was in the Jeep when I bought it. It is a 1978 CJ6. After doing some research I don't think the Dana came from the factory in 78 so I have no idea what it's history is. This is the first locker I have dealt with.
I get the loud pops as many here have described, usually on acceleration or when shifting. Scared the heck out of me the first time, thought the rear end fell out!
The question though is related to how it locks up.
If I jack up the passenger side tire and turn forward it spins the ring gear and makes the normal clicking noise. If I then turn it backwards it makes a loud clunk. Sometime after that clunk I can spin the tire and nothing in the rear end spins - tire is basically free wheeling.
Is this normal? Trying to go through the Jeep and make sure everything is working properly. After the clunking noises I wanted to make sure the rear end was solid.
Thanks for the help
From comparing pictures the locker looks like it is model 187SL16C

79CJGA is offline   Reply With Quote
Unread 04-17-2014, 04:52 AM   #2
Mike Romain
Registered User
1986 CJ7 
 
Join Date: Nov 2007
Location: Off the Grid in Chester Grant, Nova Scotia, Canada
Posts: 13,148
The test I have seen and read about is to jack up both tires and then spin one. If the tire on the other side spins the same way, your traction device is working, if the other tire spins the opposite way, you diff is acting like an open diff.
__________________
Mike
86/00 CJ7 Laredo, 33x9.5 BFG AT's, 'glass nose to tail in '00, 'New' frame,wires and plumbing in '09. Carter BBD Carbed 4.0 HO in '10.
89 YJ Renegade. BBD Carbed 4.0 HO. Locked front and rear with 33x9.5 BFG AT's
Some Canadian Bush Jeep Runs and Build Photos: http://mikeromainjeeptrips.shutterfly.com (10 new albums added Sept 16/10)
Mike Romain is offline   Reply With Quote
Unread 04-17-2014, 08:10 AM   #3
CSP
Registered User
 
Join Date: Aug 2002
Location: Colorado
Posts: 12,296
A Detroit is only going to lock when power is applied via the driveshaft. Freewheeling is normal if it's not under power.
CSP is offline   Reply With Quote
Unread 04-17-2014, 10:17 AM   #4
cj7ole
Registered User
1984 CJ7 
 
Join Date: Jul 2009
Location: Highland, Michigan
Posts: 390
Welcome! Get it on some gravel and give enough power to spin the tires. If both spin your good to go. DL's are fairly bulletproof. But they can be scary, having had one for 15 years. Sometimes a sudden acceleration or let-off on the go pedal while on pavement will give you a quick sideways jerk as there is lots of slop in the differential occasionally causing one tire to do all the pushing or pulling. Mine chirps the tires on every acceleration while turning and pulling out into traffic. And on a slow turn in a parking lot you will hear a gravelly noise like a bad bearing. And the worst is every once in a while, the tires will bind up on pavement and when it lets loose, it will sound like you broke something. Not real user friendly, but good in the sand.
__________________
'84 CJ7, '07 5.3 LMG Chevy, D300, 4L60e, 33's, 4.10, rear Detroit Locker, FG Tub, HOK Tangelo Pearl
Build: http://www.jeepforum.com/forum/f22/ole-jays-cj7-5-3-chevy-swap-1287392/
cj7ole is offline   Reply With Quote
Unread 04-17-2014, 11:24 AM   #5
80cj
Web Wheeler
 
80cj's Avatar
1980 CJ5 
 
Join Date: May 2002
Location: Hawaii
Posts: 5,797
Quote:
Originally Posted by Mike Romain View Post
The test I have seen and read about is to jack up both tires and then spin one. If the tire on the other side spins the same way, your traction device is working, if the other tire spins the opposite way, you diff is acting like an open diff.
A Detroil Locker will never spin the wheels in the opposite direction as the diferential contains no gears, only dog type clutches. Here is some interesting info and a test procedure.:

http://4x4icon.com/offroad/detroit/detroit_noslip.htm
80cj is offline   Reply With Quote
Unread 04-17-2014, 02:44 PM   #6
LumpyGrits
Registered User
1985 CJ7 
 
Join Date: Jul 2010
Location: The Mojave Desert Palmdale Ca. U.S.A.
Posts: 4,827
Quote:
Originally Posted by CSP View Post
A Detroit is only going to lock when power is applied via the driveshaft. Freewheeling is normal if it's not under power.
THIS X2.
A 'Detroit Locker' is NOT a limited slip. A D/L, LOCKS your axle as if you are using a 'spool'.
Get your Jeep on some loose sand/dirt and you should be able to spin the BOTH rear tires with ease.
No, the D/L was not OEM. A power-loc LSD was.
LG
__________________
Have'n you along, is like loose'n 2 good men
LumpyGrits is online now   Reply With Quote
Unread 04-17-2014, 06:27 PM   #7
79CJGA
Registered User
 
Join Date: Apr 2014
Location: Duluth, GA
Posts: 2
Thanks for all the great responses. I was not expecting so much good info so quickly!.
It does spin both tires in soft dirt fine. Sounds like everything is normal, at least as normal as these things get.

This forum is a wealth of great info. Keep up the good work!
79CJGA is offline   Reply With Quote
Unread 04-18-2014, 04:43 AM   #8
Mike Romain
Registered User
1986 CJ7 
 
Join Date: Nov 2007
Location: Off the Grid in Chester Grant, Nova Scotia, Canada
Posts: 13,148
Quote:
Originally Posted by 80cj View Post
A Detroil Locker will never spin the wheels in the opposite direction as the diferential contains no gears, only dog type clutches. Here is some interesting info and a test procedure.:

http://4x4icon.com/offroad/detroit/detroit_noslip.htm
That is good to know, thanks. Seeing as I have one front and rear on my new YJ, it is good to know how they work.
__________________
Mike
86/00 CJ7 Laredo, 33x9.5 BFG AT's, 'glass nose to tail in '00, 'New' frame,wires and plumbing in '09. Carter BBD Carbed 4.0 HO in '10.
89 YJ Renegade. BBD Carbed 4.0 HO. Locked front and rear with 33x9.5 BFG AT's
Some Canadian Bush Jeep Runs and Build Photos: http://mikeromainjeeptrips.shutterfly.com (10 new albums added Sept 16/10)
Mike Romain is offline   Reply With Quote




Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.