Newbie here. Transfer case or..? - JeepForum.com
Reply
 
LinkBack Thread Tools
post #1 of 16 Old 09-09-2019, 06:25 PM Thread Starter
jpn2dfire
Registered User
 
jpn2dfire's Avatar
1979 CJ7 
 
Join Date: Sep 2019
Posts: 16
Newbie here. Transfer case or..?

This is the first I’ve ever owned. And I’m learning a lot already. Two weeks ago I bought a 1979 automatic CJ7 8 cylinder. It has front locking hubs that I think someone added? If I unlock the hubs the jeep won’t move. The front driveshaft continues to spin as it should, but the rear driveshaft will not spin. If I lift the Jeep off the ground both driveshafts spin as they should even under a load by pressing on the break. Ofcourse, unless I press hard enough to stop them. So, I can only drive it with the front hubs locked. I’m just confused, because it seems to work fine lifted off the ground. Any help would be great. Do I have a bad transfer case? Also, the 4 Wheel Dr. switch inside the glove box just seems to spin around and not do anything.

jpn2dfire is offline  
Sponsored Links
Advertisement
 
post #2 of 16 Old 09-09-2019, 08:21 PM
RiverandSand
Registered User
1980 CJ5 
 
Join Date: Jun 2016
Location: Yuma
Posts: 76
Garage
By the sounds of it you have a Quadra-Trac all wheel drive jeep. Unlocking the front hubs will cause the situation you describe by allowing the unit to think it's slipping there by putting all of the traction power to the front wheels. The knob in the glove box is for emergency traction lockup, it should be vacuum operated.
Look up jeeptech for more info on your setup.
Oh and welcome!
RiverandSand is offline  
post #3 of 16 Old 09-10-2019, 06:41 AM Thread Starter
jpn2dfire
Registered User
 
jpn2dfire's Avatar
1979 CJ7 
 
Join Date: Sep 2019
Posts: 16
Thanks for your help. I did some more reading on this. I still don’t understand. Why are the lock hubs there if the Jeep puts all the power to the front thinking it’s slipping? Also, when it’s in park or any gear, if the front hubs are not locked then the Jeep will roll like it’s in neutral.
jpn2dfire is offline  
 
post #4 of 16 Old 09-10-2019, 09:20 AM
RiverandSand
Registered User
1980 CJ5 
 
Join Date: Jun 2016
Location: Yuma
Posts: 76
Garage
You will find owning a cj these things were subjected to all kinds of mods by POs, some good some not so good. A PO may have swapped in a non QT front axle or added the locking hubs for some reason.
RiverandSand is offline  
post #5 of 16 Old 09-10-2019, 10:16 AM Thread Starter
jpn2dfire
Registered User
 
jpn2dfire's Avatar
1979 CJ7 
 
Join Date: Sep 2019
Posts: 16
From what I’ve described, does it sound like its functioning properly? I’m just worried to drive it if not. And the whole thing about if the front hubs aren’t locked, the Jeep will roll like it’s in neutral no matter what gear it’s in.
jpn2dfire is offline  
post #6 of 16 Old 09-10-2019, 10:48 AM
Fourtrail
Registered User
1974 CJ6 
 
Join Date: Dec 2007
Location: Illinois
Posts: 3,969
Yes the tcase is functioning correctly. It sounds like the e-drive switch is not. If you are worried about someone unlocking the hubs and your Jeep rolling away, then order a couple of these and swap out the hubs.


https://www.morris4x4center.com/driv...ge-999396.html

80 CJ-5, 74 CJ-6, 56 CJ-5
Fourtrail is offline  
post #7 of 16 Old 09-10-2019, 11:32 AM
Spieg8
Registered User
1984 CJ8 
 
Join Date: Jun 2013
Location: Denver
Posts: 1,888
Make sure you have 6-bolt lockouts before you order the drive flanges linked above. If the PO made some swaps, you could have 5-bolt.

When I was younger, I thought I was Don Quixote... turns out I'm just another donkey-hootie.
Spieg8 is offline  
post #8 of 16 Old 09-10-2019, 11:44 AM Thread Starter
jpn2dfire
Registered User
 
jpn2dfire's Avatar
1979 CJ7 
 
Join Date: Sep 2019
Posts: 16
Great. Thank you. Why would it roll when in park or any other gear when the front hubs aren’t locked?
jpn2dfire is offline  
post #9 of 16 Old 09-10-2019, 11:47 AM Thread Starter
jpn2dfire
Registered User
 
jpn2dfire's Avatar
1979 CJ7 
 
Join Date: Sep 2019
Posts: 16
While we are talking about the transfer case... when accelerating from stop, if I don’t start very slowly there is a loud knocking noise under my feet.once I’m moving it stops. Only happens when accelerating from a stop. Would that be the chain loose? I’ve read those can go bad.
jpn2dfire is offline  
post #10 of 16 Old 09-10-2019, 01:20 PM
Fourtrail
Registered User
1974 CJ6 
 
Join Date: Dec 2007
Location: Illinois
Posts: 3,969
Quote:
Originally Posted by jpn2dfire View Post
Great. Thank you. Why would it roll when in park or any other gear when the front hubs arenít locked?

hard to explain and I haven't found a good visual that shows it well. your transfercase has an open differential in it that allows you to go around corners just like the differential in the axles. so just like the axles, if one tire is in the air (front hubs unlocked) then the jeep can roll.


Quote:
Originally Posted by jpn2dfire View Post
While we are talking about the transfer case... when accelerating from stop, if I donít start very slowly there is a loud knocking noise under my feet.once Iím moving it stops. Only happens when accelerating from a stop. Would that be the chain loose? Iíve read those can go bad.

yes, you could have a loose chain, but you could also have a bad ujoint. need to climb underneath and check everything for looseness.

80 CJ-5, 74 CJ-6, 56 CJ-5
Fourtrail is offline  
post #11 of 16 Old 09-10-2019, 02:23 PM Thread Starter
jpn2dfire
Registered User
 
jpn2dfire's Avatar
1979 CJ7 
 
Join Date: Sep 2019
Posts: 16
Sounds great. Thanks again! I’ll be doing some more digging into it when I get off work in the morning.
jpn2dfire is offline  
post #12 of 16 Old 09-11-2019, 12:24 AM
BagusJeep
Web Wheeler
 
BagusJeep's Avatar
1981 CJ7 
 
Join Date: Jul 2009
Location: Bali
Posts: 6,943
Check all U joints, POs seem not to have grease guns and the poor things are often dry and full of metal dust. I found one once which had transformed the round shaft into square, surrounded by finely ground metal and rusty pins. The vibrations gave it away.

BagusJeep lives in Bali.

1981 CJ7 258ci - Bagusjeep
1984 CJ7 258ci - Puthijeep
1981 J20 258ci - Gladys
1951 Willys CJ3A/MB/M38 - Little Willy
1995 Cherokee 4.0 - CHEROKEE
BagusJeep is offline  
post #13 of 16 Old 09-11-2019, 05:53 AM
jeepdaddy2000
Registered User
 
jeepdaddy2000's Avatar
1971 CJ5 
 
Join Date: Jan 2002
Location: Eagle Point
Posts: 8,220
A couple of quick notes on the Q trac.


Stock units have a limited slip diff. Do not allow the front driveline to spin with a hub disengaged as it will wear out the unit. This is why everything spins with no load.



They came with drive flanges bolted to the front axles. The only reason to convert to hubs is to install a Mile Marker part time kit. If your rig doesn't have the MM kit, I would recommend a conversion back the the flanges.



The clunking noise under acceleration (heavy ratcheting sound) is usually caused by a stretched chain banging over one of the sprockets in the t case. This is the one big downfall of the system, as the chain drives both the front and rear drivelines, causing a more rapid degradation of the chain. The chain stretch can be checked through the drain hole at the bottom.



They run a special fluid so if you drain it be sure to get some. We used to use a non detergent 30wt and LS additive as an alternative. Worked fine and a lot cheaper.


Insure your emergency drive is working. Engage it and unlock the hubs. The Jeep should move normally. If it doesn't, then you need to check the vacuum hoses and the vacuum motor on the rear of the unit.

The duty of a patriot is to protect his country from it's government
Thomas Payne
jeepdaddy2000 is offline  
post #14 of 16 Old 09-12-2019, 05:32 AM Thread Starter
jpn2dfire
Registered User
 
jpn2dfire's Avatar
1979 CJ7 
 
Join Date: Sep 2019
Posts: 16
They have 5 bolt lockout hubs.

All the u-joints look good.

The e-4 four wheel drive is not working. So I’m going to have to check the vacuum and pump.

I think it’s the chain on that t-case. I’m going to start with changing the fluid and see what I can figure out.
Thanks guys!
jpn2dfire is offline  
post #15 of 16 Old 09-12-2019, 11:33 AM
Spieg8
Registered User
1984 CJ8 
 
Join Date: Jun 2013
Location: Denver
Posts: 1,888
They do make 5-bolt flanges similar to the 6-bolt. I'd recommend you get a pair.

When I was younger, I thought I was Don Quixote... turns out I'm just another donkey-hootie.
Spieg8 is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.



Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may 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 Off
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome