[sticky smith]

New to this but would have thought a electric prop shaft/diff drive with existing front end would solve the age old VCU issue, and only be needed or selected as and when. So power and use would be lower and integration just buy means of roadspeed feedback. Any thoughts or experience? Obviously I already have the Freelander which is otherwise sound!

 

[LrBen]

I thought about this for my Freelander quite a bit. However space is the main issue, there isn't that much underneath to fit the motor. Then you still need to fit batteries, controller and charger.

The VCU issue is only caused by bad maintenance. It's far easier to refurbish it every 70k miles and keep your tyre wear even.

 

[sticky smith]

You are right about the space, especially as the old fuel tank has to be retained. I was thinking of the engine doing the charging as the (electric) power use would be light except in cases of front wheels losing grip.
Re life of the VCU, from new it only lasted about 50k, and the replacement about 25k! And that is not off-road. Local Land rover specialists have been trying to persuade me to remove the prop shaft for years. When I did it was like the brakes had been on all the time. Now I'm back to getting 44 mpg again just like when new. Diesel does have it's good points. Thanks for your input!

 

[sticky smith]

The cost of a VCU is about the same as the current value of my Freelander!

 

[LrBen]

We don't own Land Rovers to make smart spending decisions! Check out Bell Engineering for Freelander drive train refurbs.

There is a chap on the Open Inverter forums doing a fully electric Freelander. Nissan leaf motor into the gearbox.

 

[sticky smith]

We don't own Land Rovers to make smart spending decisions! Check out Bell Engineering for Freelander drive train refurbs.
Yes, very helpful guy. I got a refurb IRD unit from him previously because the VCU had worn it so much (I couldn't believe the small pinion size to connect the prop shaft at that end - it had a lot of backlash because of the wear.)

There is a chap on the Open Inverter forums doing a fully electric Freelander. Nissan leaf motor into the gearbox.
Will check that out, thanks.

Re the smart spending decisions, my Evoque - recently sold with only 23k on the clock after 7 years - had a complete failure on the power steering. LR absolutely refused to contribute, though eventually they parted with 70% of the cost and I got a 12 month warranty too. My successful tactics are available FOC on request!

 

[brian_]

The first post threw me initially, because in an EV conversion context "VCU" usually means "vehicle control unit", which is a processor (electronic control unit) that coordinates other components such as the motor controller with the rest of the car.

I agree that an entire electric drive system is an extreme alternative to a replacement viscous coupling unit (VCU), although if you want a hybrid that's one way to get it. Some production hybrids (most notably Toyota transverse-engine hybrids, such as the Highlander, RAV4, and now even optionally the Prius) drive the rear wheels only electrically... this would be similar, and it might even be possible to use a Toyota drive unit instead of adapting a motor to the Freelander's rear final drive unit.

Unfortunately, unless you add a generator to the drivetrain at the front as well, the only sources of energy for this rear drive would be what you store in the battery when it is charged while parked, and the little bit you recover in rear-only regenerative braking. The engine's alternator is not much for charging (and not highly efficient), and using it would require another DC-to-DC converter (for ~12 V to whatever you use for high voltage). You can charge when there is excess engine power available by running the rear motor as a generator while driving the vehicle with the engine, but this "through the road" charging is very inefficient.

 

[brian_]

Local Land rover specialists have been trying to persuade me to remove the prop shaft for years. When I did it was like the brakes had been on all the time.

I assume if giving up on the VCU and rear drive, you would not just remove the propshafts (ahead of and behind the VCU, if you have the configuration that I have seen, which is a Freelander 1), but also remove the rear final drive and axle shafts (because they're just causing drag with no incoming shaft turning).

 

[brian_]

The cost of a VCU is about the same as the current value of my Freelander!

If your Freelander is only worth £700, then it's hard to see the logic of adding an electric rear drive system...

 

[brian_]

And just because I found this hilarious...
Some Honda CR-V owners have apparently "solved" the problems they have with their AWD system (which uses a clutch system in the rear final drive housing) by locking the stock Honda bit engaged, and adding the Freelander 1's VCU into their propshaft! Maybe that VCU isn't entirely evil.

 

[sticky smith]

And just because I found this hilarious...
Some Honda CR-V owners have apparently "solved" the problems they have with their AWD system (which uses a clutch system in the rear final drive housing) by locking the stock Honda bit engaged, and adding the Freelander 1's VCU into their propshaft! Maybe that VCU isn't entirely evil.

Better still, they could probably sell the old Honda parts to quite a few Freelander owners! A win-win!

 

[sticky smith]

I assume if giving up on the VCU and rear drive, you would not just remove the propshafts (ahead of and behind the VCU, if you have the configuration that I have seen, which is a Freelander 1), but also remove the rear final drive and axle shafts (because they're just causing drag with no incoming shaft turning).

I have just removed the VCU and prop shaft, then no problem with lip seal leaking anywhere including the rear wheels/diff. Drag is not very significant I think.

 

[brian_]

I have just removed the VCU and prop shaft, then no problem with lip seal leaking anywhere including the rear wheels/diff. Drag is not very significant I think.

There's no leakage if you entirely remove the final drive (diff), but that does mean you have to disassemble the axle shafts to get the stubs to use at the hub end, without the jointed shaft attached. It doesn't make sense to me to haul around the entire final drive for no reason at all, and even less to have it continually adding even a bit of drag for no benefit. Of course, it also makes no sense to buy an AWD vehicle and not get AWD... if you are ever going to replace the VCU (with anything), the final drive and axle shafts should stay in.

 

[sticky smith]

The first post threw me initially, because in an EV conversion context "VCU" usually means "vehicle control unit", which is a processor (electronic control unit) that coordinates other components such as the motor controller with the rest of the car.

I agree that an entire electric drive system is an extreme alternative to a replacement viscous coupling unit (VCU), although if you want a hybrid that's one way to get it. Some production hybrids (most notably Toyota transverse-engine hybrids, such as the Highlander, RAV4, and now even optionally the Prius) drive the rear wheels only electrically... this would be similar, and it might even be possible to use a Toyota drive unit instead of adapting a motor to the Freelander's rear final drive unit.

Unfortunately, unless you add a generator to the drivetrain at the front as well, the only sources of energy for this rear drive would be what you store in the battery when it is charged while parked, and the little bit you recover in rear-only regenerative braking. The engine's alternator is not much for charging (and not highly efficient), and using it would require another DC-to-DC converter (for ~12 V to whatever you use for high voltage). You can charge when there is excess engine power available by running the rear motor as a generator while driving the vehicle with the engine, but this "through the road" charging is very inefficient.

The Toyota solution looks good. Freelander drives the front wheels a feew % fasteer that the rear so that slip is needed in order to get rear wheel drive, which is a good idea. I expect LR know how much

There's no leakage if you entirely remove the final drive (diff), but that does mean you have to disassemble the axle shafts to get the stubs to use at the hub end, without the jointed shaft attached. It doesn't make sense to me to haul around the entire final drive for no reason at all, and even less to have it continually adding even a bit of drag for no benefit. Of course, it also makes no sense to buy an AWD vehicle and not get AWD... if you are ever going to replace the VCU (with anything), the final drive and axle shafts should stay in.

Best solution is probably to wait until it dies and start with a clean sheet of paper! Can't be long, it's 23 years old.

 

[LrBen]

If that's a 23 year old diesel Freelander I would keep hold of it for a few more years at least. Those L series engines are getting very rare.

 

[sticky smith]

The first post threw me initially, because in an EV conversion context "VCU" usually means "vehicle control unit", which is a processor (electronic control unit) that coordinates other components such as the motor controller with the rest of the car.

I agree that an entire electric drive system is an extreme alternative to a replacement viscous coupling unit (VCU), although if you want a hybrid that's one way to get it. Some production hybrids (most notably Toyota transverse-engine hybrids, such as the Highlander, RAV4, and now even optionally the Prius) drive the rear wheels only electrically... this would be similar, and it might even be possible to use a Toyota drive unit instead of adapting a motor to the Freelander's rear final drive unit.

Unfortunately, unless you add a generator to the drivetrain at the front as well, the only sources of energy for this rear drive would be what you store in the battery when it is charged while parked, and the little bit you recover in rear-only regenerative braking. The engine's alternator is not much for charging (and not highly efficient), and using it would require another DC-to-DC converter (for ~12 V to whatever you use for high voltage). You can charge when there is excess engine power available by running the rear motor as a generator while driving the vehicle with the engine, but this "through the road" charging is very inefficient.

The Toyota solution looks good. Freelander drives the front wheels a few % faster that the rear so that slip is needed in order to get rear wheel drive, which is a good idea. I expect LR know how much the life of a VCU is and what causes most wear, but they might not wish to get into that territory.