76 Jeep with Quadratrac Question

[level4designs]

I have a couple questions about the quadratrac. It has a 360, with a TH400, and a quadratrac case. The case has the 2 air nipples and hoses, but there is no switch in the glove box at all, just the end of the 2 air hoses that regulate the emergency drive.

Now it's not in emergency drive right now, which is fine, but with it in limited slip mode (regular drive), is it front wheel drive, then slippage causes the back to kick in?

reason I ask is that I went to drive it the other day, unlocked the front hubs it has (dana 44), and it would not move. I looked under it and the front driveshaft was spinning slowly, the hubs were unlocked, so it didn't move, but the rear was not engaging?

tonight, I went out and removed the rear driveshaft, spun the rear shaft, which also spun the front shaft, hooked it up, then it DID drive with the front hubs unlocked?

is my case going bad? or what inside would cause it to do this? chain slippage?

[Jim_Lou]

Will is the expert here on Quadratrac. I'll let him know about this post so he can answer it. Your problem isn't chain slippage, though. When it slips you get a terrible buzzing/ratcheting sound and don't move.

[level4designs]

Thanks, I would appreciate any help here from some experts... I took it out again today, and I have about 6 inches of snow, so I went to a small hill. I have ARB lockers front and rear, and locked it up. when I go uphill forward, it sometimes is locking, othertimes the rear doesn't engage. If I come down and go in reverse and spin the tires, it is usually working...

so my guess is something is wrong in the inside, possibly a stripped gear? or the limited slip is not operating correctly...

I wish I could engage it into emergency drive, but I have no vacuum or switch, just 2 tubes...

as a side note, what would be a good replacement? If I go with another case, would I need a new axle as the quadratrac is off-center? what is a good combo? or do they make a dana 44 that is off-center?

[Jim_Lou]

There were D44s on Quadratrac CJ7s, and I'm pretty sure they were narrow-track like yours, but it doesn't sound like you have an axle problem. I doubt that there's anything wrong with your AMC20.

As for replacing the Q-Track, there were several transmission and transfer case combos that came in CJs of your series. Up until the early '90s they used the Dana 20 transfer case, and later the Dana 300. Both are very good and strong conventional part-time cases, and either will fit. And of course all Jeeps with them came with a centered back axle, which you will need if you install either of the PT cases.

I just called Will and he said that he'd check in on the board in about 20 minutes.

And by the way, welcome to the board! I didn't notice that you just made your first post.

[WILL]

So far everything sounds like it is working correctly. From the dana 44 and 360 I am guessing this is a J-truck or wagonner/cherokee. The quadratrac is a sturdy and reliable transfer case. The only things that usually go wrong are the vacuum lines or the chain stretching. If you email me an address to jeeper360 at yahoo, I have an extra switch I can send you.

[CJDave]

Greetings Quadra-Trac owner. The Superb Borg Warner case that is in your Jeep is adequate in every way. It has a heavy chain that drives the outside of a "Barrel Differential" that splits the power. The differential has some cone clutches in it that make it hard to SLIP the differential; the thinking was that if they didn't DO that, you would slightly spin one front wheel when you took off from your buddy's gravel driveway. Of course that's an error in their thinking, and the NV 242 case as used in the later Grand Cherokee proves that. I run my Grand in "open center" quite a bit and don't have a problem with scratching gravel ....unless I WANT to to show off of course. So....ideally, the QT case should have NO clutches in it so the Jeep can drive with less strain and have better fuel economy..well, slightly better anyway. So.... sometimes the clutches in a QT are worn enough that it actually DOES act like it has a totally "open center". Now the person who had your Jeep did a little trick that got him a slightly better drive, and that was he unlocked ONE front hub and put the QT in Emergency Drive. That way the front shaft tumbled, but the front axle had one side unlocked so it ran nice and free. You wouldn't want to unock both sides because then it would be possibe to wear out the spider gears in the front pumpkin. I KNOW, I KNOW, it;s kind of confusing, but if you think about it long enough it'll become clear to you. If both sides were unlocked, one axle could stop and the other roll like mad on the spider gears. Soooo WWILL can send you a vacuum switch and then by trial and error.....the front nipple is for Emergency Drive (Locked Differential) and the rear nipple unlocks it.... you can get set up. Daily Drive would be Emergency WITH ONE HUB UNLOCKED. Mud would be Emergency Drive with both hubs locked. Snow would be hubs locked and cast in regular drive.

[level4designs]

I appreicate that, that's really upstanding of you... and it is actually a 360 with a th400, and is in a 76 CJ7... it's cool.

so, why unlock one hub? why not just leave them both in?

I was actually on an incline on ice road, so I just sat there and spun the wheels easily enough, while hanging my head out the window... it seems perhaps the clutch inside is dying? with ARB lockers in both front and rear, locked, all 4 tires should spin? but the back woudl only spin some of the time, while it should be spinning no matter what? I would spin the wheels in reverse, the back woudl work, spin them forward, and sometimes it would spin the back, sometimes it wouldn't?

[CJDave]

Yes, Grasshopper, you must memorize these words: "Open Center All-Wheel Drive". Notice little one that I did not say FOUR WHEEL DRIVE. ALL-WHEEL DRIVE is NOT FWD. In All-Wheel drive you have THREE...count them,....THREE differentials. The ones in the front and rear axles, AND.....the one in the trasfer case. The power winds it way from the pistons to the crankshaft to the tranny to the transfer case drive chain and to the outer sprocket of that barrel differential in the QT case. WHICHEVER driveline turns the easiest is where it goes from that point. THEN it gets to THAT axle and to that axle differential and which ever axle shaft turns the easiest is where it goes from there. If little cousin Leroy spilled a bowl of ice cream in Uncle Bob's concrete driveway in July, and you backed over it with the left rear tire, your Jeep would sit there and spin, because THAT'S HOW OPEN CENTER ALL-WHEEL DRIVE IS SUPPOSED TO WORK. Every wheel is free to go at it's own speed; which is why they work so well in slop and ice. Sometimes after driving home in a blizzard I have to reach down and "pin" my center differential because my Grand Cherokee will not climb up the one inch-plus step into the garage, The rear axle is on pure ice, so guess where the power goes? So I have to shift into what in your Jeep would be known as Emergency Drive...you lock up the center differential. Once I do that, I have basically got standard four wheel drive, just like a 1942 Willys Jeep. THAT is what you have when you flip that QT into "Emergency" and "pin" the center differential, regular four wheel
drive. Now as I mentioned in the last post, you CAN drive all over in "E" with ONE front wheel unlocked if you want to run as free as possible. That will make it quick and easy to hop out and engage the hub if need be.

[level4designs]

Ahh, obie-one... you are making me happy!!! so essentially nothing should be wrong with my case... so now when I put the brain stimulous to my spine, down the hip bones, to the femur, past the knee joint, into the lower toes, and push the gas, I have nothing to fear

once I get the e-switch installed and working, it will function as needed, locked!!

gracias...

[Jim_Lou]

Bingo!

You learn quickly, Young Grasshopper