Transmission wind up.?

Submitted: Tuesday, Jun 27, 2006 at 18:09
ThreadID: 35336 Views:4054 Replies:11 FollowUps:8
This Thread has been Archived
Hi.

A mate of mine (hear we go!!) has a late model pajero ,and is concerned about towing a 1.5 - 2.0 t on van. Evidentley when you select low range it also engages 4wd, so if in steep country and you have to stop and start again and need low range to do so , is the transmission going to wind up and stop you? this is on the hard stuff, he reckons it winds up if in low range backing up his drive way!!. Can anyone shed some light on this, is this normal with other makes?, or does he have a prob. He was'nt impressed when i told him to buy a Landy, Caus they dont do it.

Thanks Axle.
Back Expand Un-Read 0 Moderator

Reply By: disco driver - Tuesday, Jun 27, 2006 at 18:51

Tuesday, Jun 27, 2006 at 18:51
Hi Axle,
If your mate has to use low range to get moving in steep country, perhaps he should not have the van on the back.
If he gets wind up backing up his driveway, solve the problem by taking the front hubs out of lock.
Used to do that back in the old series2 days.
Cheers

Disco
AnswerID: 180670

Reply By: Member - MrBitchi (QLD) - Tuesday, Jun 27, 2006 at 18:59

Tuesday, Jun 27, 2006 at 18:59
How late is late?
Just about every 4wd will engage 4WD when you select low range. Only way you can stop it is to disengage the hubs, if they're manual. If they're auto you're stuck with it, unless you do some modification to bypass 4WD in low range.
If the Paj is a post 2000 model (NM/NP) then 4WD will engage every time you select low range. Having said that, I can't really think of a scenario where this would be a problem. You'd have to be in an offroad situation to make low range a necessity to move off and, that being the case, transmission windup is not a factor as it's not a problem on dirt roads.
The Paj has plenty of power to pull it's rated towing capacity on sealed surfaces without having to resort to low range.

AnswerID: 180671

Reply By: Exploder - Tuesday, Jun 27, 2006 at 19:01

Tuesday, Jun 27, 2006 at 19:01
Can’t see why it wouldn’t be able to get going agene, unless we are talking a ridiculously steep incline.

Just make that toque converter work for its money LOL, it’s a Auto I am guessing.

How is he going to get it out of Low when he gets up to speed?, because he isn’t going to be able to leave it in Low the hole way up a hill on solid ground as he will damage something IMO

AnswerID: 180673

Follow Up By: Member - Axle - Tuesday, Jun 27, 2006 at 19:12

Tuesday, Jun 27, 2006 at 19:12
Its a manuel 2.8 Turbo intercooled , He seems to be concerned about taking off with a van on a hill . Dunno might be his driving??.
0
FollowupID: 436929

Follow Up By: Exploder - Tuesday, Jun 27, 2006 at 19:25

Tuesday, Jun 27, 2006 at 19:25
Has he Given it a try?, Might be the Go, Just load the thing up and find a nice steep hill with minimal traffic and see if it can take off. Might need to work the clutch a bit to get underway< But a slightly toasted clutch is better than a cooked driveline, I reckon.
0
FollowupID: 436931

Reply By: DiD 05 Paj - Tuesday, Jun 27, 2006 at 19:23

Tuesday, Jun 27, 2006 at 19:23
I've had the similar problem when I back the car trailer (loaded) up the drive, you cant disconnect the front hubs. I use low range on bitch'm its not a big problem unless you turn alot and go lock to lock. It works very well !!
AnswerID: 180680

Reply By: Smithy51 - Tuesday, Jun 27, 2006 at 20:19

Tuesday, Jun 27, 2006 at 20:19
Hi Axle,
In reply to wind up yes it does happen on most 4x4s I have personal experience to this as a mechanic of many years ago, seen a transfer case slit from wind up. The reason the transfer case split was that the vehicle was driven for 40 miles on a bitumen surface with no slippage of the tyres on the bitumen as would occur on a loose surface. As stated by other members if u have free wheeling hubs disengage them. By doing this your front hubs will have no connection with the drive of the axles. As stated with auto hubs u can't do anything about this wind up. There is no real drama using low 4x4 for short distance on a hard surface. You will notice that the tyres will try to skip to release this wind up. U may find that in some 4x4s after u have driven foward a distance u may have to put it into reverse & move backward to get the transfer selector lever to release.

Regards Smithy51
AnswerID: 180696

Follow Up By: Member - Axle - Tuesday, Jun 27, 2006 at 20:34

Tuesday, Jun 27, 2006 at 20:34
On these later models (2000 onwards) are the auto hubs mechcanically controlled or is it electric? If electric then maybe a switch could disengage.?
0
FollowupID: 436956

Reply By: Notso - Tuesday, Jun 27, 2006 at 20:21

Tuesday, Jun 27, 2006 at 20:21
You'll always get ransmission wind up unless you have a centre diff (Full time 4wd).

Wind it up too much you'll break an axle. If you have manual hubs you can leave the front unlocked, but don't put too much power into it with only the rears driving as the torque can also breakthe power train somewhere in Low Low, without the fron hubs locked in as all the torque is being transmitted through the rears. That includes under power and on over run

AnswerID: 180699

Reply By: Des Lexic - Tuesday, Jun 27, 2006 at 20:32

Tuesday, Jun 27, 2006 at 20:32
I have been under the impression that you got transmission windup when turning corners etc where the outside wheel turns at a different rate than the inside wheel and without slipping on a loose surface, wind up occurs and could break something. Therefore if you are driving in a straight line, wind up should not occur.
Am I wrong?
AnswerID: 180705

Follow Up By: fisho64 - Wednesday, Jun 28, 2006 at 00:01

Wednesday, Jun 28, 2006 at 00:01
yes unfortunately! It can only happen in this way if you have a diff lock engaged. Normally the diff takes care of this.
But if 4wd and hubs are locked on a hard surface, the very slight tyre size difference will slowly load it up till the weakest point goes, axle or transfer case usually I understand.
Vehicles with constant 4wd use a third differential at the transfer case to take care of windup.
0
FollowupID: 437024

Follow Up By: Member - Roachie (SA) - Wednesday, Jun 28, 2006 at 08:05

Wednesday, Jun 28, 2006 at 08:05
Des, I believe you are right............and so is fisho.............

I'm guessing we are only talking about relatively short distances here....enough for the 4by and trailer to get going to the top of a steep track; maybe 500 meters?

Fisho is right about trans wind-up , even in a straight line, on a hard surface...... if the distance travelled is substantial. EG: you wouldn't want to travel across the Nullabor with hubs locked and in 4x4 as the very slight differences in tyre diameter etc "could" cause some issues with the drive-line.

I solved the problem by junking my auto-locking hubs and fitting selectable AVMs; job's right!!!!!

Cheers

Roachie
0
FollowupID: 437041

Reply By: GaryInOz (Vic) - Tuesday, Jun 27, 2006 at 20:35

Tuesday, Jun 27, 2006 at 20:35
Wind up will only occur if there is a difference in the speed of the front axle to the rear, usually by turning the steering wheel off centre. Another cause could be due to different sized tyres front/rear, or heavily loaded rear tyres such as when towing, which alters the effective diameter.

Using low range with the front diff disengaged via the hubs runs the risk of overloading the rear diff, the extra torque is designed to be spread across the four wheels.

2Lo is good for precision driving such as lining up on a trailer to couple up, but generally is not recommended for heavy lugging.
AnswerID: 180707

Reply By: fezkez - Tuesday, Jun 27, 2006 at 21:06

Tuesday, Jun 27, 2006 at 21:06
Hi Axle,
I had a pajero before the patrol, a 3.0 litre NH. I seem to remember that it was " shift on the fly ". I am quite shaw that it has the option of consant 4WD and also a centre diff lock if needed. Take a look at the gear levers they should give you a clue and then refer to the manual. I don't think running in consant 4WD is a problem for late model Pajeros.

Cheers Nino.
AnswerID: 180717

Follow Up By: fezkez - Tuesday, Jun 27, 2006 at 21:08

Tuesday, Jun 27, 2006 at 21:08
Sorry, Take out Shaw and insert Sure.......Brainfade
0
FollowupID: 436972

Reply By: Member - Barry C (NT) - Wednesday, Jun 28, 2006 at 00:16

Wednesday, Jun 28, 2006 at 00:16
Axle what year was the Paj. My 3.0L pulls current 1.5 tonne boat up very steep boat ramps no probs.

If I go into low range it AUTOMATICALLY locks the dif lock (front and read axle locked together not each individaul diff), and diff wind up is almost instant.

Other problem I had with 2.8 l turbo diesel in another Pajero is it was gutless down low revs and from standing start. Had 2 tonne boat then and problems you describe, without turbo going the 2.8 has no grunt at all, so not surprised this problem exists.

Maybe rethink tow vehicle, we have just gone to LC79 ute in preparation for desert trips and to eventually pull 2.5 - 3t van off road. Horses for courses

Hope this makes sense Barry.
AnswerID: 180758

Follow Up By: Member - Axle - Wednesday, Jun 28, 2006 at 11:46

Wednesday, Jun 28, 2006 at 11:46
Hi barry, its a 2000 model 2.8 TI exceed.
0
FollowupID: 437083

Reply By: Patrol22 - Wednesday, Jun 28, 2006 at 12:20

Wednesday, Jun 28, 2006 at 12:20
I faced a similar problem with my 2.8tdi manual patrol and getting moving on steep inclines. Rather than slip the clutch excessively I choose to use low range...and voila no problem. To negate the windup issue I changed out my auto hubs with a set of AVM manual hubs. I think a lot of people are dreaming if they think they can tow to capacity from a standing start on a very steep incline - on or off road without slipping the clutch to a greater or lesser degree depending on how many cubic inches of grunt you have. Auto transmissions are another story but if you have a transmission oil temp gauge on a smaller engined auto....just watch how much the temp rises as the torque converter takes up the slip.
AnswerID: 180811

Follow Up By: Member - Barry C (NT) - Wednesday, Jun 28, 2006 at 21:46

Wednesday, Jun 28, 2006 at 21:46
Looks like a solution here and agree with your comments Patrol22.
0
FollowupID: 437201

Sponsored Links

Popular Products (13)