Driving on front wheels only

[dom14]

Hey guys,
I've been wondering...............
In case of a drama like the rear diff blows up, is it possible to drive on front wheels only for some decent distance??!!
If so, how long do you think a GQ patrol can be driven that way and how fast can we safely go?

I'm speculating on a temporary solution like disconnecting the rear drive shaft, letting the rear wheels turn without
the drive train.
I'm not too sure whether it's possible when blown diff is the cause of it(or blown pinion bearing, etc rather).
I know the pinion gear and ring gear failure is rare in Patrols. It would most likely a bearing failure.

Since there's no hub connect/disconnect arrangement in rear, when the wheels turn, the axle and the diff would
turn as well.
So, perhaps the diff would keep turning like it's coasting, with minimal noise, unlike when the drive
shaft is connected to the damaged or worn diff???!!

Any ideas?

[Rossco]

It's possible to drive on front wheels only if necessary, however there are not many instances where this would be beneficial in a Patrol i would reckon. The main reason to do this in my opinion would be to isolate the tail shaft if there was a problem and take it out. If rear diff has issues it will still be spinning, i know with no load but still have potential to go bang or lock up. Wheel bearings can't be isolated and axles can't be removed like full floating type in yotas. Driving in 4wd carefully might be an option to help take load off. Depend on the situation i guess. Bent or broken lower control arm this will help or potentialy a situation to concider to drive with front wheels only carefully to get out of the poo.

[TimE]

Many years back a mate with a Perado (thanks Jase) blew a rear diff in the bush. We pulled the diff out and removed the crown wheel (it was just about toothless), reassembled and he drove home on the front wheels, about 150ks.

[Wizard52]

Also many years ago, we were camped on Double Island beach when this young couple walked in to camp about 7pm in the rain. They were on their honeymoon.
He was a mechanic and as usual his own car was the last one to be worked on. The unis on rear tail shaft had seized so no way to get back to Noosa.
We gave them a feed and a couple of drinks and when the rain stopped and with a bit of help and borrowed tools from us drunken idiots, he dropped tail shaft and drove down the beach in front wheel drive to return next morning with a carton of XXXX.
I think it was a Jeep but not sure.
I bet they still remember that trip.

[dom14]

Thanks for the posts guys.

So far from what I understood, I reckon it is possible with a GQ with some caution.
The biggest problem with GQ is the axle is a semi floating one.
Which means the axle can't be removed without the aid of a hydraulic press.
I've been having enough trouble trying to remove the bearing nut which I couldn't get it off even with
heavy banging with a drift.(some 350Nm torque on it, but I reckon way more than that in my one).
So, unless there's a clever backyard method to get the bearing off the axle, I reckon the only solution
is to cut the axle with a hacksaw or a grinder. But if the problem with the diff doesn't cause it to lock,
then there's a good chance driving for a decent distance by removing the rear drive shaft.

Am I right about that?

Another solution would be to pull the diff centre out and remove the crown wheel as TimE mentioned above.
That's also possible with a Patrol, is it not?
That's probably the least damaging solution in such a situation.
Am I right about that?

Yes, there's no doubt the right tools are necessary. But, most of us carry some tools in the back of the fourby anyway.
The above mechanic fella who was in his honeymoon was an exception(or may be not, he was in a too happy mood to
carry any tools with him I reckon) :D

Thanx

[krbrooking]

Thanks for the posts guys.

was in a too happy mood to
carry any tools with him I reckon) :D

Thanx

I think he was only concerned about using one tool that weekend. Lol


Sent from my iPhone using Tapatalk

[dom14]

I think he was only concerned about using one tool that weekend. Lol


Sent from my iPhone using Tapatalk

Yep, obviously too excited to remember even that one tool might need backup tools from the tool box to get going.
He wasn't the only one who's too euphoric to remember the value of the backup tools though.
I'm sure we all done that. :bananadancing: :D

[Rumcajs]

Thanks for the posts guys.


The biggest problem with GQ is the axle is a semi floating one.
Which means the axle can't be removed without the aid of a hydraulic press.
I've been having enough trouble trying to remove the bearing nut which I couldn't get it off even with
heavy banging with a drift.(some 350Nm torque on it, but I reckon way more than that in my one).
So, unless there's a clever backyard method to get the bearing off the axle, I reckon the only solution
is to cut the axle with a hacksaw or a grinder. But if the problem with the diff doesn't cause it to lock,
then there's a good chance driving for a decent distance by removing the rear drive shaft.

Am I right about that?

Another solution would be to pull the diff centre out and remove the crown wheel as TimE mentioned above.
That's also possible with a Patrol, is it not?
That's probably the least damaging solution in such a situation.
Am I right about that?


Thanx

GQ or GU or anything else, you can't remove diff centre unless you remove axle shafts first! So for semi floating hubs this is not on the side of the road fix in the hurry and you have to refit them back in after the diff centre is removed in order to be able to refit and roll on the wheels. I'll rather pay for the tow truck or shred the diff instead than do this on the side of the road or in the middle of desert.

If you have full floating hubs than it is much easier, if you want the diff not to spin just pull the axle shafts out (or just one if open diff) plug the holes with rag or tape them and disconnect rear prop shaft and drive with front drive only as long as you like.

Cheers

[dom14]

Yeah, but paying for a tow truck may not be a luxury in the middle of the desert or far out nowhere.
So I think the time spent on pulling out both axles and then pulling out the diff centre and removing the crown wheel
is well spent.
Full floating axle is not a luxury in Patrols(at least in GQ).
I wonder why Nissan decided to do it that way.
Semi floating axles are PITA IMO. Very hard to replace the bearing without special tools,
let alone removing the axles in an emergency situation like above.

So, removing the crown wheel sound like a good solution to prevent the diff from getting locked from existing damage.

So, if I understood correctly,
Assuming calling for roadside assistance is out of question in a particular situation,
For a GQ Patrol,
Removing the diff centre and then removing the crown wheel and then driving on front wheels is a valid solution to get
the vehicle to somewhere where you can get the diff fixed.

Am I right about that?

[Rumcajs]

Yeah, but paying for a tow truck may not be a luxury in the middle of the desert or far out nowhere.

I'll rather have it skull dragged out to nearest tow truck pick up...



So I think the time spent on pulling out both axles and then pulling out the diff centre and removing the crown wheel
is well spent.

Have you ever done such thing as removing diff centre? I think you'd reconsider the "time well spent" especially in the middle of the desert, its bad enough job in the workshop ....

Unless you are at CSR, spending 2 days removing and refitting the rear diff centre with countless opportunities for stuff ups or fails



Full floating axle is not a luxury in Patrols(at least in GQ).I wonder why Nissan decided to do it that way.

Its cheaper and not really needed for the GVM loads.... leaf sprung GUs with H260 have full floating hubs.


Semi floating axles are PITA IMO. Very hard to replace the bearing without special tools,
let alone removing the axles in an emergency situation like above.

Well, there you are, answering your own question.


So, removing the crown wheel sound like a good solution to prevent the diff from getting locked from existing damage.

So, if I understood correctly,
Assuming calling for roadside assistance is out of question in a particular situation,
For a GQ Patrol,
Removing the diff centre and then removing the crown wheel and then driving on front wheels is a valid solution to get
the vehicle to somewhere where you can get the diff fixed.

Am I right about that?

Only if you are really really desperate and out of all options.....I'm a pro and honestly I'd have refused to be that desperate, rather yank the fuel hose off and strike a match.........:blowup: I like my Patrol but it is not worth that much pain....

In any case this scenario is almost impossible on Patrol GQ or GU alike, it only applies to Swiss cheese diffs from Toyota and their owners are known to be desperate :harhar: so is it really GQ you are concerned about?

B/R

[mudnut]

Read this thread about
removing rear wheel
bearings without a
press.

http://www.nissanpatrol.com.au/forums/showthread.php?21203-Rear-wheel-bearings-amp-seals&highlight=rear+wheel+bearings

[awloelxf]

If you need to drive using front axle, the easiest way is to remove rear propellershat. No damage will occur.

[dom14]

If you need to drive using front axle, the easiest way is to remove rear propellershat. No damage will occur.

I hope you are very knowledgeable & correct in that mate.
I know removing the drive shaft prevents the engine from putting any load on the damaged diff.
But, the free turning rear wheels will still keep putting a 'load' on the damaged diff.
It probably won't lock even with a damaged crown wheel, pinion gear or bearings, but still can make noise I reckon.
How bad the noise is something I wouldn't know.
If I'm wrong about that, I am really happy to listen and learn.

[dom14]

I'll rather have it skull dragged out to nearest tow truck pick up...

That can be 500km skull drag in middle part of the tiny Island of Australia :D
Even that won't be an option if you are on solo.


Have you ever done such thing as removing diff centre?

Yes,


I think you'd reconsider the "time well spent" especially in the middle of the desert, its bad enough job in the workshop ....

It's not too hard once vehicle rear is jacked up high enough. I would imagine it even make lot 'easier' on a hoist.
GQ diff centre is only 40kg heavy unit, so it's not that bad.
The original large hemisphere 4:3 rear diff is still on the bench, half way through the rebuild job. I just need to get the tooth pattern & backlash fine tuned.
The currently running one is a backup one(same ratio) from a GU, which is a smaller hemisphere LSD diff centre. When ready, the original GQ diff will go back in.
The backup GU diff centre will end up with somebody else who may want it.
I have no intention to carry a backup diff with me everywhere I go. :D


Unless you are at CSR, spending 2 days removing and refitting the rear diff centre with countless opportunities for stuff ups or fails

I'm not sure what a CSR is, but it shouldn't take 2 days with the right tools. It's a PITA job, no doubt.
The real challenge is to get the rear diff jacked up high enough safely. The rest is spanner, wrench, socket job.


In order it should be,
1)Lifting the rear if necessary
2)removing axle+hub assembly on both wheels
3)Draining the diff oil before the above(need the diff bung tool, I made my own with a 12-15mm bolt)
4)Remove the drive shaft and remove the diff centre
5)Remove the crown wheel
6) put the diff centre back and fit the axles and wheels

But, I think most of the time we should be able to getaway with only removing the drive shaft.


Its cheaper and not really needed for the GVM loads.... leaf sprung GUs with H260 have full floating hubs.

Yes, and GQ utes use H260 as well, so I'm assuming some GQ utes come with full floating rear axles if not all!!!
It sounds like fully floating rear axles and leaf springs go hand in hand?!


Only if you are really really desperate and out of all options.....I'm a pro and honestly I'd have refused to be that desperate, rather yank the fuel hose off and strike a match.........:blowup: I like my Patrol but it is not worth that much pain....

I'm in love with my Patrol. The misus is only their to cook the meals for long trips. :thumbup:
I would rather leave misus in the desert and recover the Patrol. :D


In any case this scenario is almost impossible on Patrol GQ or GU alike, it only applies to Swiss cheese diffs from Toyota and their owners are known to be desperate :harhar: so is it really GQ you are concerned about?

Yes, GQ diffs are pretty hardy. Everybody says so, it must be true. I'm the only unlucky one who happens to end up with rear diff pinion bearing failure.
But, the crown wheel and pinion gear was spotless. I'm actually more worried about RB30 GQ gearbox failure and clutch failure, rather than diff failure.
Diff failure has a roadside solution as above. Gearbox failure or clutch failure means, I'm screwed. If I'm on solo and in the middle of nowhereville, then I'm
terminally screwed. :D

I reckon GU smaller hemisphere rear LSD is more prone to failure than GQ larger hemisphere LSD. But, that's the LSD part though.
At least that's what I've been told by diff specialists, hence the reason for decision to rebuild the original GQ diff and use the GU diff only as an interim solution.
With the LSD stuffed up, the diff can still keep going like an open diff though(assuming I'm correct about that), which is not as desperate as the situation above.

[dom14]

Read this thread about
removing rear wheel
bearings without a
press.

http://www.nissanpatrol.com.au/forums/showthread.php?21203-Rear-wheel-bearings-amp-seals&highlight=rear+wheel+bearings

Thanx mate.
I had no idea the above thread has existed.
A real life saver. It's time to read it now.

[Rumcajs]

Read this thread about
removing rear wheel
bearings without a
press.

http://www.nissanpatrol.com.au/forum...wheel+bearings

There you go, so if only removing axles to get the diff centre out then it is as easy as unbolting and sliding the whole assembly out.

I still want to know what happens when the ends of the shafts have no support as they rotate inside the tube and not splined/meshed to sun gears, are they going to "whiplash" around?


I'm not sure what a CSR is...

Canning Stock Route, a track that runs from Halls Creek in the Kimberley region of Western Australia to Wiluna in the mid-west region. With a total distance of around 1,850 km (1,150 mi) it is the longest historic stock route in the world.

The route is now a popular but challenging four-wheel drive adventure..........

Canning Stock Route (https://en.wikipedia.org/wiki/Canning_Stock_Route)

Honestly, I don't know what exactly is your problem with diffs but your thoughts border extreme at best desperate/paranoid at worst. With the
thoughts like that you might as well contract full repair support vehicle with lifting equipment, safety stands etc.....and all replacement parts.....

What is your plan, crossing Great Western Desert unassisted, forging your own tracks like Len Beadell not expecting to see any humans for 6 months? Here is the free tip: don't do it alone!
Or are you preparing for the next round Camel Trophy?

Because even at CSR you'll hardly be alone most of the time.

Is it all just to save couple of grand? Well, load her up mate because with all that stuff you'll need to be sure to be sure, the chassis is probably going to crack/break so make sure you pack a welder too....

I reckon Iveco Daily 4x4 LT (http://iveco.com.au/index.php/off-road/daily-4x4) is your best bet then. With 5.2 T GVM and 3.2 towing capacity you can carry the whole spare GQ with ya :coffeetime:

So a nagging question remain, how do you lift the GQ high enough in soft sand and also secure it so it doesn't crush you while you are underneath?

Look it is doable, but it is extreme sport IMHO, I saw photos of someone changing rear springs on the beach, vehicle not looking safe at all lifted on two Hi-Lifts, one mistake and it would be all over.

I've done some crazy things on the side of the road (engine rebuild/gearbox swap, clutch replacement) and each time I swore never again.

My back is ruined!

So yeah

1,) Lift the truck up and secure on something (gravity is a biatch)
2,) Drain oil
3,) Remove wheels, brake callipers and hub/axle assemblies
4,) Removed prop shaft (I'd loosen the bolts while vehicle is still on wheels, and don't forget to pack wheel chocks)
5,) Remove all that it is in the way of the diff centre
6,) Remove diff centre (had enough yet?)
7,) Somehow hold on to the diff centre while while bolts for the bearing caps of the crown wheel (this where tow bar attachement with vice comes handy,make sure you mark the caps so pack a centre punch too)
8,) Remove crown wheel

Reassemble in reverse order then drive in front wheel drive mode back to civilization, congrats you have saved yourself some pennies but most likely ruined your health in the process.

Also pray that unsupported axle shaft ends don't smash the diff/axle housing as they wobble around

Crazy, right!

B/R

[dom14]

There you go, so if only removing axles to get the diff centre out then it is as easy as unbolting and sliding the whole assembly out.

I still want to know what happens when the ends of the shafts have no support as they rotate inside the tube and not splined/meshed to sun gears, are they going to "whiplash" around?

I think with a GQ rear diff, it shouldn't be that of a big problem. Crown wheel removed, the rest of the bits appear to be able to put together
inside the diff casing. Also, once the axle housing is fastened to the diff housing the "whiplash" should be minimum, hopefully.

Canning Stock Route (https://en.wikipedia.org/wiki/Canning_Stock_Route)


Honestly, I don't know what exactly is your problem with diffs

There's no problem with diffs. Just put forward a question about hypothetical but probable situation on the road anywhere.
Since I did the diff rebuilding myself on my rear diff, I thought it might be good idea to have a back-up plan in case my diff job fails.


but your thoughts border extreme

probably a little bit, but healthy imo.


at best desperate/paranoid at worst.

Rarely. I try very hard not to be desperate or paranoid, but I think now I am. :))



With the
thoughts like that you might as well contract full repair support vehicle with lifting equipment, safety stands etc.....and all replacement parts.....

I won't, I don't think I can afford. I'm driving a twenty plus year old vehicle. That says a lot where I stand in the food chain.


What is your plan, crossing Great Western Desert unassisted, forging your own tracks like Len Beadell not expecting to see any humans for 6 months?

Thought has crossed my mind. But, I would be pushing my luck with the GQ RB30 though.


Here is the free tip: don't do it alone!

I agree. But, even though I'm not as crazy as Steve Irvin. I prefer to do take a calculated risk after doing some early home work.
But, it won't be anything like a true adrenalin junkie attempts.


Or are you preparing for the next round Camel Trophy?

May be one day. But, atm I dont think I have enough experience to have crack at it :)


Because even at CSR you'll hardly be alone most of the time.


Is it all just to save couple of grand?

Nope. just like to keep my GQ as long as I can practically do, instead of abandoning it in the middle of nowhere 'cos the cost of recovery can be more than the value of the vehicle. It's a kinda sentimental connection to inanimate objects like a Patrol. :D



Well, load her up mate because with all that stuff you'll need to be sure to be sure, the chassis is probably going to crack/break so make sure you pack a welder too....

That's what I do. But, I don't carry a welder, just few welding sticks and an extra battery or two. Haven't had any vehicle chassis cracks yet.
But, did have caravan frame cracking and suspension parts breaking, etc. Welding sticks and batteries can be pretty handy. Instead of ruining the days of
the trip, I could carry on thanks to simple preparations like that.


I reckon Iveco Daily 4x4 LT (http://iveco.com.au/index.php/off-road/daily-4x4) is your best bet then. With 5.2 T GVM and 3.2 towing capacity you can carry the whole spare GQ with ya :coffeetime:

Man, if I can afford that rig, I would rock n roll. and you would be the first to join the ride as a form of gratitude for pointing that to me :cheers:


So a nagging question remain, how do you lift the GQ high enough in soft sand and also secure it so it doesn't crush you while you are underneath?

I would be pretty careful to take my RB30 as it is on sand that soft for any (un)healthier length of time. If shite happens regardless of that, I would have to deal with when it happens. At home it wasn't that hard with some creativity, even on uneven ground, but dunno about sand balancing a vehicle with stuffing stuff underneath. If worse come to worse, I might have to abandon the vehicle, but not before crying like a baby for few hours. :D


Look it is doable, but it is extreme sport IMHO, I saw photos of someone changing rear springs on the beach, vehicle not looking safe at all lifted on two Hi-Lifts, one mistake and it would be all over.

Yeah, that's crazy. I have a reputation for being extra cautious under vehicles and usually stuff extra stuff like wheels underneath for redundancies, especially when I'm doing a project on solo.


I've done some crazy things on the side of the road (engine rebuild/gearbox swap, clutch replacement) and each time I swore never again.

There you go. You've done your share of the unthinkable stuff. Though I can't imagine a way to replace a GQ clutch or swap a gearbox without carrying some
heavy gear.
GQ gearbox failure or clutch replacement on the side of the road is where I would draw the line. It's such a heavy biatch, I would rather save my back in that case. But, having said that, if there's a way to fix the clutch of a GQ on the side of the road, I'm very much interested in knowing how. I wouldn't wanna rebuild an engine on the side of the road. Even with all the bit and pieces, it can take an awful amount of time. I prefer to make sure the engine is in good nick before long trips. head gasket failure is ok to fix on the side of the road though. I usually carry a spare head gasket kit(no I don't carry a spare cylinder head. :D, but I do carry a bottle of what you call liquid glass or sodium silicate, just in case )


My back is ruined!

Mine already has. I have a TENS machine that paralyses living shite of any part of the body, so much so, it's halfway between getting electrocuted by
230V & 110V. Pain ceases to exist temporarily.


So yeah

1,) Lift the truck up and secure on something (gravity is a biatch)
2,) Drain oil
3,) Remove wheels, brake callipers and hub/axle assemblies
4,) Removed prop shaft (I'd loosen the bolts while vehicle is still on wheels, and don't forget to pack wheel chocks)
5,) Remove all that it is in the way of the diff centre
6,) Remove diff centre (had enough yet?)
7,) Somehow hold on to the diff centre while while bolts for the bearing caps of the crown wheel (this where tow bar attachement with vice comes handy,make sure you mark the caps so pack a centre punch too)
8,) Remove crown wheel

Reassemble in reverse order then drive in front wheel drive mode back to civilization, congrats you have saved yourself some pennies but most likely ruined your health in the process.

As the other blokes above has pointed out, all the above process may not be necessary. It may be just removing the drive shaft. Yeah, it's doable, as long as there's a safe way to raise the rear of the vehicle to get under it. Yeah, it's true, depend on the location where shite hit the fan, it may not be a luxury. Either way, to me, it's more about the saving the vehicle that I like to keep, not all about saving money. Most of these diff repairs aren't worth the time when try to fix them in the backyard. You can save few dollars, but can cost awful lot of time. But the experience is pretty handy in the bush. I think that is the very reason for the existence of the technical part of this forum.


Also pray that unsupported axle shaft ends don't smash the diff/axle housing as they wobble around


Lets say the crown wheel has already been removed. Yes, I know removing the crown wheel is easier said than done. But the rest of the differential case need to be put back the way it was and fit it on the differential housing. Easier said than done. But, the diff is already stuffed. so, you don't need to worry about things like preload or backlash anymore. Thats better left to a professional. So, if I'm correct about the GQ rear diff, sliding and resting the axles where it was in the diff should be possible.
Another thing is since GQ diff I'm talking about is semi floating, it shouldn't wobble as much as we suspect. Of course, it sure will ruin the inner axle seals.
But, they are only few dollars.


Crazy, right!

Yes

[Naukai]

Yeah I bent my control arms and snapped the pinion gear... Had to pull the diff mid track and remove the broken gear and reassemble the diff, removed the tail shaft so it was only the front getting me home.

Took me half a day to pull out the diff and reassemble, I only had a high lift and spare tire to rest the car on.

Drove Okay from the Wattagans back to Sydney... and around the shops for a couple of weeks

Yes I wanted to torch the car!!! No towie was going to get to me. Would I do it again... yes!!!! these are the things you have to do as a 4b owner (and drive hard tracks)

Ash

[dom14]

Yeah I bent my control arms and snapped the pinion gear... Had to pull the diff mid track and remove the broken gear and reassemble the diff, removed the tail shaft so it was only the front getting me home.

Took me half a day to pull out the diff and reassemble, I only had a high lift and spare tire to rest the car on.

Drove Okay from the Wattagans back to Sydney... and around the shops for a couple of weeks

Yes I wanted to torch the car!!! No towie was going to get to me. Would I do it again... yes!!!! these are the things you have to do as a 4b owner (and drive hard tracks)

Ash

Just wondering mate. Bending control arms seem to damage the diff gear.
I'm wondering the mechanics behind this.
Shouldn't the uni joint adapt and save the diff pinion before you stop?

[Naukai]

The lower control arms were bent like a banana causing the angle at the unis to be too great which then snapped the pinion. Yes there was lots of head scratching and "I've never seen that before"...

Don't go driving with comp trucks with standard arms, learnt a good lesson that day, lucky there was a winch truck with us and with a double line pull and another vehicle snatching/towing we were able to get the car back on the flats and change out the diff.

One thing to remember is if you are only running on the front without the rear tail shaft you will not have a handbrake..

[dom14]

The lower control arms were bent like a banana causing the angle at the unis to be too great which then snapped the pinion. Yes there was lots of head scratching and "I've never seen that before"...

Don't go driving with comp trucks with standard arms, learnt a good lesson that day, lucky there was a winch truck with us and with a double line pull and another vehicle snatching/towing we were able to get the car back on the flats and change out the diff.

One thing to remember is if you are only running on the front without the rear tail shaft you will not have a handbrake..

Oh, crxp!!!! Can you believe that didn't cross my mind at all until you mentioned??!! :icon_bonk:
It's easy to forget these things.
GQ hand brake is bullet proof, until we remove the drive shaft. :D
It's the price to pay for having four wheel disc brakes.

[Rossco]

Wouldn't it still work tho, as the front & rear shafts are locked together when in 4wd?? . . . In theory anyway! !

[mudnut]

If you are worried
that having only the
nuts holding
the handbrake drum
then disassemble the
top uni joint and use
the flange.