5.0 awd transfer case

[AWDRIVEN1999]

So, I've gone through three of these stupid things, each one the person said "oh yeah, great condition.." whatever... Anyways, I need to know if these things are rebuildable.. a guy here in town says he can do it, but won't give me a price, so I'm a little leary of it... Any help would be greatly appreciated.. I hate running around with this thing w/o awd.. it likes to roll away if I don't chock the wheels...

 

[drdoom]

Yes they are, I saw pics on here of one repaired in the truck.

 

[1997XLTRollover]

4406 swap will solve all those issues, along with more power and better fuel economy.

 

[SWIGIN]

My Uncle who has been a mechanic for like 40 years told me the AWD units are roughly $700 to fix.

For $100 I got a BW4406 and both drive shafts needed for the swap.....no brainer.

 

[SoNic67]

4406 swap will solve all those issues, along with more power and better fuel economy.

Will do none of those. The poor gas mileage comes from big V8 turning at idle and the whole mass of metal that needs to be moved after every stop.

All the defective AWD cases are from cars that owners decided to remove the front drive shaft "to save gas". And now they have a blown Viscous Coupler.

 

[AWDRIVEN1999]

yeah, the previous owner removed it for "fuel ecomony", and now it doesn't work. I'll have to do a swap i guess. That sounds like the best option. Thank everyone.

 

[masospaghetti]

Will do none of those. The poor gas mileage comes from big V8 turning at idle and the whole mass of metal that needs to be moved after every stop.

All the defective AWD cases are from cars that owners decided to remove the front drive shaft "to save gas". And now they have a blown Viscous Coupler.

The TC can be defective while not necessarily having a bad viscous coupling. We've beaten this horse to death before. While definitely not ideal, many users (me included) have driven many thousands of miles with no front shaft without destroying the VC.

But to the OP: Yes, the unit is rebuildable. I did it myself last year. There's not many parts and I don't remember needing any exotic tools (you may need a blind bearing puller if you are installing new bearings - parts stores rent these). Even if the VC is bad, its like a $200-300 part. Chain is $75 or so. I don't remember how much a bearing kit is, but not more than $100.

Installing a used 4406 is going to be a complete crapshoot. The 4406 is far more complex and has a lot more parts to fail. I would fix your 4404 before trying to convert. I doubt a 4406 will yield any meaningful gain in power or economy, it will add weight compared to the 4404.

 

[Turdle]

Will do none of those. The poor gas mileage comes from big V8 turning at idle and the whole mass of metal that needs to be moved after every stop.

All the defective AWD cases are from cars that owners decided to remove the front drive shaft "to save gas". And now they have a blown Viscous Coupler.

Show us your 4406 swap

 

[1997XLTRollover]

Since when does the 4406 swap not help power and fuel mileage? Every thread I've read on this forum has said that it feels like a whole new truck power wise and that fuel mileage went up too.

 

[SoNic67]

You read. Did anybody really MEASURE that? Or is just plain wishful thinking?
I know that, my AWD, can "roll" in neutral like nobody's business. That to me means the friction in drivetrain is minimal. If anybody with a 4406 around me wants to make a comp run, I am game...
Start both with the same speed, same tire pressure, same weight and see how long we roll in "N" from like 35mph (so the air drag won't matter).

When you compare the drivetrain resistance with the other loses (engine, inertia, even the tire rolling resistance), it is minimal. And drivetrain includes more than just the TC!!! It's also four bearings, four axles, two differentials... A plain TC swap won't do anything about those friction points.

 

[Mounty99]

Will do none of those. The poor gas mileage comes from big V8 turning at idle and the whole mass of metal that needs to be moved after every stop. All the defective AWD cases are from cars that owners decided to remove the front drive shaft "to save gas". And now they have a blown Viscous Coupler.

Good post.

 

[masospaghetti]

You read. Did anybody really MEASURE that? Or is just plain wishful thinking?
I know that, my AWD, can "roll" in neutral like nobody's business. That to me means the friction in drivetrain is minimal. If anybody with a 4406 around me wants to make a comp run, I am game...
Start both with the same speed, same tire pressure, same weight and see how long we roll in "N" from like 35mph (so the air drag won't matter).

When you compare the drivetrain resistance with the other loses (engine, inertia, even the tire rolling resistance), it is minimal. And drivetrain includes more than just the TC!!! It's also four bearings, four axles, two differentials... A plain TC swap won't do anything about those friction points.

Agreed.

Think about this. Even a claimed 10 hp gain (which would be borderline impossible to notice from the driver's seat) would mean that the 4404 is absorbing 10 hp at full throttle. 10 hp is 7450 watts of power. Presumably it would all be absorbed by the viscous coupling since this is the only unique component of the 4404. Can you imagine how hot the VC would get? Have you felt a 100 watt light bulb? Now multiply that by 74 times.

Also think about this. The 2WD model is rated at 1 MPG better than the AWD. So at an absolute maximum you would get 1 MPG better. In reality, the 4406 is still driving a front driveshaft, differential, axles, and bearings, so it has almost all of the same drag points as the 4404. And again - it weighs more.

 

[CDW6212R]

Agreed.
...
Also think about this. The 2WD model is rated at 1 MPG better than the AWD. So at an absolute maximum you would get 1 MPG better. In reality, the 4406 is still driving a front driveshaft, differential, axles, and bearings, so it has almost all of the same drag points as the 4404. And again - it weighs more.

That is a very good thought. Compare the 2WD 302 truck to the AWD version, that will be the maximum you could gain with a BW4406 swap.

I'm going to have both an AWD Explorer and one with the A4WD BW4406 unit. I'll dyno test the one when it's stock, but I haven't decided whether to do it before or after the 4406 swap. I'm interested in the gains from a large dual 3" exhaust, not the TC swap. I might be able to do the exhaust before the 4406, but I wouldn't want to dyno it an extra time just to test the affects of the 4406. I'm already planning on 3-4 tests, another would be nuts.

 

[SWIGIN]

Agreed.

Think about this. Even a claimed 10 hp gain (which would be borderline
Also think about this. The 2WD model is rated at 1 MPG better than the AWD. So at an absolute maximum you would get 1 MPG better. In reality, the 4406 is still driving a front driveshaft, differential, axles, and bearings, so it has almost all of the same drag points as the 4404. And again - it weighs more.

The 4406 is only driving the front driveshaft when you have it in 4hi or 4lo. In 2hi or 2wd (however it is spelled out) 100% of the available power is sent straight through to the rear driveshaft.

To stop the front D shaft and axles from turning you need to have hubs that unlock.

 

[Turdle]

The 4406 is only driving the front driveshaft when you have it in 4hi or 4lo. In 2hi or 2wd (however it is spelled out) 100% of the available power is sent straight through to the rear driveshaft.

To stop the front D shaft and axles from turning you need to have hubs that unlock.

^^^ this is a good post.

I think the AVM hub conversion will be my next "Mod"

 

[SoNic67]

The 4406 is only driving the front driveshaft when you have it in 4hi or 4lo. In 2hi or 2wd (however it is spelled out) 100% of the available power is sent straight through to the rear driveshaft.

Really? What is disconnecting the shaft from the wheels? NOTHING!
Wheels spin, axle shafts spin, front diff is spinning... the front driveshaft it will still spin.
It will still have friction loses. More, even if you have manual hub disconnects, you still have bearings there that add friction.
The biggest loss on highway cruising is the pumping loss in cylinders at partial load. That's why some manufacturers 'suspend' cylinders today. Or use turbo's to allow for lower cylinder sizes (less pumping losses at partial loads).
In city, is the friction in brakes at every stop light.

There is no sensible gain to get from that swap.

 

[Turdle]

Sonic, Why is it so hard for you to grasp no power is going to the front in 2wd mode. That is the whole reason for having a selectable transfer case.

 

[SoNic67]

It doesn't matter at all if power flows or not. Friction it will still be there. Car still stops eventually if you put it in neutral, doesn't?

The reason for a TC is that is way cheaper than a limited slip differential like in AWD case. Throw in some clutches and you are done.

Please see my sig.

 

[Turdle]

It doesn't matter at all if power flows or not. Friction it will still be there. Car still stops eventually if you put it in neutral, doesn't?

The reason for a TC is that is way cheaper than a limited slip differential like in AWD case. Throw in some clutches and you are done.

Please see my sig.

That is not what you said. You said power was applied to the front even in 2wd

Pay attention. The "friction" you speak of which was always there, can be eliminated with a disconnect hub conversion.

The benefits of the 4406 outweigh the drawbacks. IMO. The awd is weak and will just be a constant plague, along with the cv joint on the front drive shaft. If you'd ever look close you'd see the cup is just a trap for rocks,and, the angle of the driveshaft will drive the trapped rocks into the rubber boot. Once this happens the cv joint soon follows. Unless you pull the driveshaft to inspect it after every drive on a gravel road, who knows?

 

[SoNic67]

I didn't say such thing! I said that the drivetrain is still spinning, TC connected or not. It's spinning because the wheels are spinning. Pushed from rear or from all for corners, they still spin.

About the disconnecting hubs - unless the hub is magnetic levitating, friction it will be always there. That's why there are so unpopular now - no gas mileage advantage.