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Which Patrol automatic or manual

Posted: 20 Jun 2009 14:31
by AJ Dup
Hi Guys

Like you can see Im new here after a lot of homework I decided on a patrol for my 1st 4x4. But my problem now is I dont know which one to buy the manual or automatic? I need your help?

Which one is better offroad? ANd why?

Regards A.J.

Re: Which Patrol automatic or manual

Posted: 20 Jun 2009 15:54
by Gerrit Loubser
Hi A.J. and welcome! Congratulations on your choice of vehicle and all the best in your search.

Manual vs. Automatic for use off the tar is a great question and has often been debated. There is no clear cut answer to me. Here are some thoughts to ponder:

A manual transmission has a positive connection between engine and wheels and maximizes engine braking for controlled hill descents. In an automatic there is no positive connection between engine and wheels due to the presence of a torque converter which transfers drive via hydrodynamic action (unless the torque converter is mechanically locked, which generally does not happen in low speed, high torque situations or on the overrun). This means that an automatic has less engine braking for two reasons: firstly higher gearing is employed due to the fact that torque is multiplied hydrodynamically by the torque converter when accelerating (but not under engine braking) and secondly slip occurs in the torque converter. It also means that the driver can not use the throttle to control the vehicle to the same extent as on a manual vehicle.

In conditions where a direct drive connection is important, such as when crawling over rocks at low speed or on steep descents a manual transmission might be preferable. On the other hand one has to remember that there will always be a hill so steep that engine braking alone will be insufficient. For these conditions you need to learn to drive using careful control of the brakes too (despite what they might teach you on the 4x4 training courses). If you are able to master brake control, i.e. applying brakes by feathering them to avoid wheels locking and techniques such as left-foot braking while driving through the brakes with the right foot controlling the throttle then an automatic can work very well in these conditions too.

If you find yourself in mud the auto has the advantage that you can pull away very gradually and prevent wheelspin. On sand this can also be beneficial as can the ability to change gears very rapidly whithout much interruption of power delivery. Once again, very skillful drivers can achieve similar results with a manual vehicle.

In sand the automatic gearbox is likely to work the torque converter hard and this generates heat. The transmission cooling system typically is unable to cope with extreme use of this nature and might overheat. When this happens, a warning light will illuminate and the transmission will have to rest a while with the vehicle idling to cool down.

Back on the tar one has to consider that the manual vehicle might easily be 10% to 15% more fuel efficient than its auto equivalent. On the other hand, the auto is very convenient in stop-start driving and does not have a clutch that wears (although it does have transmission fluid that typically needs to be replaced rather more frequently than on a manual transmission).

Re: Which Patrol automatic or manual

Posted: 20 Jun 2009 16:37
by AJ Dup
Thanks Gerrit thats a mouthfull.
This torque converter what will happen if this overheats and long cooling time does it need before you can carry on?

Re: Which Patrol automatic or manual

Posted: 20 Jun 2009 18:24
by Saltman
Hi AJ

Great explanation of the differences by Gerrit!

It also depends on the type of terrain, type of driving and usage (touring conditions) you intend using the Patrol for.
For instance, I bought the manual as I do the following with it:
1) tow a trailer and/or a Semi-rigid duck - especially mountain passes are a pleasure as I am able to select the correct gear for the job - 4th gear is 1:1 and very strong! This is were Gerrit's comment about the torque converter temperatures becomes an issue.
2) camp out in the bush where there is no support of any nature - if I need to I can jump start the car through a variety of manual methods, where the auto might prove difficult to get going.
3) Due to the remoteness of some of our travels, I can still travel without a clutch, but an auto goes nowhere without the torque converter and its associated oil!
4) I have more control over which gear I pull away in, or drive. This is an advantage in mud and water and over rocky terrain, however might also be a negative, particularly in serious sand, where the seamless gearchanges of the auto is an advantage. It just means I have to be very quick with the hand-foot coordination for quick manual shifts!!
5) the manual is only available in GL spec - a lot less creature comforts, BUT also a helluva lot less that can go wrong!!! The GL has mainly manual controls - manual aircon, manual gearbox (comes out of a bleddie truck I believe), no electronic steering wheel controls, no speed control system (damn), no electric seats, no sunroofs, etc etc
6) Certainly seems to be lighter on fuel than the auto ... but fuel consumption is relative anyway!

Soooo, which one: Here is my take:
I am obviously happy with my manual and the use I put it to. If I was an old man like JohnBoy, then I would also opt for the GRX Auto ... the creature comforts will swing it in my later years :lol:

Re: Which Patrol automatic or manual

Posted: 20 Jun 2009 19:16
by Gerrit Loubser
AJ Dup wrote:This torque converter what will happen if this overheats and long cooling time does it need before you can carry on?
If you stop when the warning light illuminates, no permanent damage will be done. Typically a stop of 10 to 20 minutes will see the temperature back under control, but it could become tedious to stop every now and then.

Re: Which Patrol automatic or manual

Posted: 20 Jun 2009 19:25
by Gerrit Loubser
Saltman wrote: camp out in the bush where there is no support of any nature - if I need to I can jump start the car through a variety of manual methods, where the auto might prove difficult to get going.
Very good point Saltman.
Saltman wrote: the manual is only available in GL spec
This is true in the case of the newer Patrols, but older ones, like my '99 4.5 can be manual and GRX spec (still no speed control, though).

AJ, are you looking to buy new or used and if the latter, how old/which model/which engine?

Re: Which Patrol automatic or manual

Posted: 21 Jun 2009 19:57
by G-MAN
Hi A.J. :welcomewave: I have had both auto and manual 4x4's. Patrol's Ive had in manual and now own a auto 4.8, best thing since sliced bread! :thumbup: The auto box is great in every terrain, just get use to left foot braking while 4x4ing and its all good. Drive both and you will know which one is for you. :mytwocents:

Re: Which Patrol automatic or manual

Posted: 22 Jun 2009 11:10
by AJ Dup
Ill be looking at a 4.8 petrol Second hand.
Thanks for all the info so far looks like its gonna be a Manual.

Re: Which Patrol automatic or manual

Posted: 22 Jun 2009 18:13
by G-MAN
If its a Patrol its all good. :thumbup:

Re: Which Patrol automatic or manual

Posted: 23 Jun 2009 08:04
by KOOS BEST
Very nice input guys, thats why this site so great.
I also prefer a manual, but a recent trip in the Kalahari going over dunes the Auto's were far superior , our manual guys as soon as we changed down we were bogged down. Never happened to any of the Auto's. I have to admit my Patrol , I could pull away from that same position to get over the crest of the dunes . The other guys had to reverse all the way back and charge the dunes again .
Koos