All wheel drive question ?

[Shayne]

The Colorado is a permanent 4x4 and power goes to all four wheels all the time . Lets say the balance of power is 50/50 to front and back .

Can i change that balance and if so how ?

 

[AndycruiserguyLomas]

Just wondered Shayne, why would you want to?

Andy

 

[silvercruiser]

I think the power is about 60% rear 40% front normally and then when you lock the centre diff its then 50/50 but i might be wrong.

 

[Gary Stockton]

Correct 60:40 rear:front split according to the manual. Locking the centre diff gives 50:50 obviously. I wouldn't have thought the open diff ratios could be alter edit - too much electrickery involved for one thing ...

 

[Shayne]

Spent about 2 hours last night reading about slip diff etc and it looks like power will go to the wheel with least resistance under normal driving conditions without difflock . This didn't make sense to me at first i was thinking "the wheel with the least grip gets most power ????" but when you consider the front passenger wheel must travel considerably quicker than the other wheels while making a right turn it makes sense .

Given the above i guess this is a pointless question .

With regards to why Andy - my truck is significantly more powerful now than when i bought it and spinning the front wheels unintentionally has become difficult to avoid which obviously is not gonna do my tyres any good . But if power will be delivered to the wheels with the least resistance regardless , altering the balance (60/40 back/front was what i had in mind) will serve no purpose as my SWB is inclined to "wheelie" (for want of a better word) under acceleration in first or second gear meaning less load and less resistance and more power to the front wheels .

 

[chadr]

Wow - your diesel must be churning out some serious torque! I've had my petrol 90 nearly 10 years and I doubt I have EVER managed to spin the front wheels on tarmac!

I'm quite mechanically sympathetic with my truck but even when I try a quick standing start on tarmac, all that happens is that it grips and goes......no drama.

 

[Gary Stockton]

Spent about 2 hours last night reading about slip diff etc and it looks like power will go to the wheel with least resistance under normal driving conditions without difflock . This didn't make sense to me at first i was thinking "the wheel with the least grip gets most power ????" but when you consider the front passenger wheel must travel considerably quicker than the other wheels while making a right turn it makes sense .

Given the above i guess this is a pointless question .

Not quite, the way I understand it is in a case of open diffs the power (force) will follow the path of least resistance so if a wheel (on any corner) has no traction for whatever reason the power will go there because it's the easiest to turn - the others won't turn. Thus engage a diff lock or have a limited slip diff and the system will compensate and force energy to the other wheels, enabling drive.

This might help explain better than me

http://youtu.be/RcRBYpccP6g

 

[Towpack]

LSD's and diff locks are completely different in there operation. A diff lock simply locks both side of the diff together. A LSD is much more complex using torque reaction to limit the amount of difference in the wheel speeds. This is where the benefit of the VC on later 80 series comes into it's own. It means you get, effectively, the benefit of a limited slip centre diff without the problems a fully locked diff would give you on normal roads. A system pioneered by Audi back in the eighties with the Quattro. LSD's are common on performance cars. I had a '74 XJ12 years ago with one. You could park with one rear wheel on wet grass or snow/ice etc, facing uphill and still drive away.

 

[Beau]

Shayne, you have a heavy foot or dump the clutch rather quick I can just about spin the wheels on tarmac dry if going round a corner,much easier with a bit of rain!

I would put your loss of grip down to your tyres though, what are you running? Would be good to see a 0-60mph run, maybe we can compare?

 

[greengrass]

My swb 90 will spin its wheels without too much provocation, mine has the D4D lump under the bonnet so running about 160ponies and a lot more torque than yours in standard form.
What sort of power do you think your running Shayne??

If you push it hard at about 20-30ish mph when going round a tightish bend 2nd or 3rd gear it will spin up the wheels and go very sideways. Caught me a bit unaware the first time it did it, it doesn't feel like a controled slide like you get in my Hi-lux when it gets out of shape.

 

[chadr]

Being SWB 90s and manual may be a factor. On my auto the TC seems to absorb any excess power/torque at lower speeds.

Sent from my GT-I9100P

 

[silvercruiser]

My auto will spin all 4 wheels and do doughnuts easily





















In the Snow

 

[Shayne]

In the Snow

I think it's very unlikely i'm running D4D like 160 horses even with an oversized exhaust , intercooler and the fuel turned up . Beau has probably hit the nail on the head , bad driving coupled with 285/75 R16's Cooper all terrain tyres is most likely the cause . It's just a shame the front tyres always take the hit the back wheels have never spun that i'm aware of .

 

[Beau]

I think it's very unlikely i'm running D4D like 160 horses even with an oversized exhaust , intercooler and the fuel turned up . Beau has probably hit the nail on the head , bad driving coupled with 285/75 R16's Cooper all terrain tyres is most likely the cause . It's just a shame the front tyres always take the hit the back wheels have never spun that i'm aware of .

Just a theory, but maybe the sudden increase in acceleration (flooring it) lifts a bit of weight off the front thus less weight on the tyres and grip so they end up easier to spin?

 

[stumog]

when a vehicle moves off the front of the car always lifts and the back drops. so a rwd car would have more grip then a fwd car would. the harder you move off the higher the front comes up then less and less grip. so driving like this does not do you any favours. i would look at a broken diff / cvs soon.
best thing to do if you want to drive fast is buy a sports car or learn to put the power in properly.
stu

 

[Shayne]

Permanent 4x4 means there must be a slip diff built in or you would be changing tyres monthly because they would all have to run at the same speed all the time without the slip . Accelerate hard and the load is transferred to the rear wheels . The slip diff puts power to the wheel/wheels offering least resistance , hence the front wheel spin .

I did say very early on my original question was pointless .

 

[stumog]

a slip diff allows the diff to slip a little then locks up to give you drive. there is no slip center diff in a 90/95. its just normal open diff that locks when you lock it. the front spines because the power goes to the wheel with least resistance and as the front has lifted so thats why the front spines. sorry but you have your idea around the wrong way.stu

 

[jonnyboy54321]

Shayne, as has been said, it's not a drag racer however, just a thought - are your rear springs very saggy letting body weight transfer backwards excessively?

 

[Shayne]

Springs are fine Jonny front comes up but the rear only dips slightly , the same question had occurred to me though . It's they way i drive and thats all there is to it i could rumble around town never getting above 1500rpm if i chose and the wheelspin would stop , but wheres the fun in that , its a toy and it begs to played with

 

[Shayne]

Found on another forum , users were discussing which oil for what -

"Let's clear up the confusion;

The Prado is an all wheel drive (AWD) hence it has a center differential. The center differential is intergrated into the transfer case (making it an AWD transfer case)

1 case, 1 oil, 1 drain plug and 1 fill plug.

It takes 1.4 lts of Hypoid gear oil, API GL-5 SAE 75w-90.

So, from front to back you have:

Front diff
Engine
Gearbox
Transfer case
Rear diff"