4 wheel drive and diffs on Isuzu Dmax

[Craig.]

I do appreciate the comfort and quietness/ general car like attributes of pickups, and in this respect the landrover is considerably outdated and suffers from many niggles to boot. But I do need 4x4 on the road too, as Beau says, the devon lanes are a complete nightmare being single tracked and covered in mud/algae, Even with 4x4 on the landrover I can get a fair bit of slippage when I tow my 3 ton digger up a hill particularly when you have to stop several times whilst going up to let oncoming cars squeeze by!

 

I would not want the same weight behind something in 2x4 in those circumstances.

 

In those circumstances you say, would cause no harm to a pick up transmission in 4x4 high or low, as any wind up would be released,

When you say you have slippage, is that with the centre diff locked or unlocked? If it is locked the transmission will, in effect be the same set up as the pick up.

[Matthew Storrs]

In those circumstances you say, would cause no harm to a pick up transmission in 4x4 high or low, as any wind up would be released,

When you say you have slippage, is that with the centre diff locked or unlocked? If it is locked the transmission will, in effect be the same set up as the pick up.

 

No that is just in low ratio, no diffs locked, I havn't yet needed to lock them yet on the road, but im sure if I was in a 4x2 rear wheel drive pickup there simply wouldn't be traction on the rear whees when pulling up a steep devon lane simply due to the lak of weight over the rear tyres, also I doubt many modern pickups are geared low enough that they could do a reasonable hill start with a genuine 3.5t in tow, I know the ranger certainly can't because we've tried it, so this means dropping into low- which means diffs are locked in a pickup- is that correct? consider there are hills round here which can be 4 miles straight drag up hill- that's a lot of time to wind up the transmission.

[hedgesparrow]

i have a navara with gear stick for 4 wheel yes not good turning as all 4 wheels being driven ok on road in high if roads not good eg snow ice well just as well leave in 2 wheel as make no difference it will slide. as for low box not a good idear made for getting out of gloop when i use mine in low box i start in first but go into second and let it drive itself with just a bit of revs. hardly had to get up the box in low if going that fast then high is going to be ok. but its not just 4 wheel its tyres if just road tyres then will not work well off road or in snow as no tread. most mordern ones have diff lock in unlike old trucks had to turn the difs on the wheels so when in 4 wheel diff will operate hence not good turning tight and yes tyres will wear quicker

[Craig.]

No that is just in low ratio, no diffs locked, I havn't yet needed to lock them yet on the road, but im sure if I was in a 4x2 rear wheel drive pickup there simply wouldn't be traction on the rear whees when pulling up a steep devon lane simply due to the lak of weight over the rear tyres, also I doubt many modern pickups are geared low enough that they could do a reasonable hill start with a genuine 3.5t in tow, I know the ranger certainly can't because we've tried it, so this means dropping into low- which means diffs are locked in a pickup- is that correct? consider there are hills round here which can be 4 miles straight drag up hill- that's a lot of time to wind up the transmission.

 

Fair enough.

 

In my experience, new type ranger, first is low enough to start off with loaded trailer on a reasonable hill. We've got some good hills/poor roads here in north wales.

 

Low range on most modern pick ups, would be the same as the centre diff locked on your land rover, not axle diff locks, but yes the manufactures wouldn't recommend driving for long distances in 4x4 on high grip surfaces.

 

If your losing traction, loaded or towing, I cant see any harm coming to transmission using 4x4.

[JimE]

Im not sure that some people quite understand how the drive system on a LR defender works.

When you have the center diff lock disengaged it will not have any more traction than a pickup with rear wheel drive. When you engage the center diff lock it is the same as other pickups in 4WD (will scrub the tyres on hard surfaces). The LR doesnt have the TC system that the pickups do though.

There is no LSD in a landrover transfer box.

 

I have been thiking about adding a switch to the 4WD in my Dmax, so I can engage low box and then turn off the 4WD so manouvering on road in lox box. I think the 4WD has a seperate fuse, so was going to see if this is possible by pulling the fuse out.

 

The TCS on the Dmax is great though, works really well in snow!

[gensetsteve]

Im not sure that some people quite understand how the drive system on a LR defender works.

When you have the center diff lock disengaged it will not have any more traction than a pickup with rear wheel drive. When you engage the center diff lock it is the same as other pickups in 4WD (will scrub the tyres on hard surfaces). The LR doesnt have the TC system that the pickups do though.

There is no LSD in a landrover transfer box.

 

I have been thiking about adding a switch to the 4WD in my Dmax, so I can engage low box and then turn off the 4WD so manouvering on road in lox box. I think the 4WD has a seperate fuse, so was going to see if this is possible by pulling the fuse out.

 

The TCS on the Dmax is great though, works really well in snow!

 

The defender is permanent 4 wheel drive with low box and diff lock. With diff lock in you have equal traction front and back but you could still spin 2 wheels as you dont have diff locks.

 

The pick ups only drive to the rear wheels. When you engage 4wd the front axle is driven and often locked so traction to both front wheels. unless you have lsd or diff lock on the back you may spin a rear wheel.

[Jonny69]

Im not sure that some people quite understand how the drive system on a LR defender works.

When you have the center diff lock disengaged it will not have any more traction than a pickup with rear wheel drive.

 

Are you sure you understand the difference?

 

On a Defender all 4 wheels are being driven until one slips.

 

On a pickup on two wheels are being driven until one slips. Until you engage 4wd.

 

Also, you can get traction control on a Defender

[Woodworks]

 

I have been thiking about adding a switch to the 4WD in my Dmax, so I can engage low box and then turn off the 4WD so manouvering on road in lox box. I think the 4WD has a seperate fuse, so was going to see if this is possible by pulling the fuse out.

 

Sound good Jim. Let us know how you get on.

 

I did have a quick chat with Roger Young today. They could do the modification but it would invalidate the warranty on all parts affected by the mod. Their view was use it how you like and if torque wind up breaks anything you would be covered by the 5 year warranty.

[farmer rod]

Are you sure you understand the difference?

 

On a Defender all 4 wheels are being driven until one slips.

 

On a pickup on two wheels are being driven until one slips. Until you engage 4wd.

 

Also, you can get traction control on a Defender

 

The traction control is standard in the dmax I think, my main gripe is that there is no bleeper if you drive along in 4wd, whereas it bleeps if you put the key in the ignition or havent put your seatbelt on

[gensetsteve]

The traction control is standard in the dmax I think, my main gripe is that there is no bleeper if you drive along in 4wd, whereas it bleeps if you put the key in the ignition or havent put your seatbelt on

 

 

 

I like your thinking I am sure a bing bong could easily be wired in with the dash light but think it would be tiresome if your are in 4x4 all day.