[Robin Miller]

Hi Guys
Took my new 2010 GU 4800 for its first drive down some super slippy Victorian tracks
and it proved such a dog its almost a show stopper, and looking for ideas on what to do about it.
Its an auto of course with no engine braking. I still have my manual 4800 and it was so much better.
It was a bit hectic so I can't be sure but I do not think the 5 speed auto fully locks up
in 1st low , there seemed to be lots of transmission slip - also not sure of the exact effect of the ABS with its "Gravel Sensor" in the above senario.
Driving thru the brakes has proved impractical when your on ice-like steep slippy rutted and rough downhills.
So we tried putting the car into reverse on the slope but the damm thing stalls out as the rear wheels overdrive the box.
I guess I first need to know for sure if the box locks solid, and if not do this but with some form of low rev protection.
I note the projects on this site which seem to use lock up mods slanted towards touring use.
Suggestions please.

Robin.

 

[hienuf]

Rockhopper or gearmaster low range gears.

I fitted 83% rockhopper gears to my auto 4.8.......The best mod ever.

 

[Robin Miller]

I think thats a pretty good mod either way Hienuf , and have the 43% ones on the shopping list but I need to find out a little more about the exact operation of the current system to make the best choice.

Simple things like knowing for sure if the transmission locks up in 1st low - and does the transmission unlock under some conditions.
Also just what effect the ABS has on things - as I might be able to come up with some form of electronic overide or hill descent control.

It sounds like your are a happy customer - do you know if there is any particular advantage to either sets of gears ?

Robin

Rockhopper or gearmaster low range gears.

I fitted 83% rockhopper gears to my auto 4.8.......The best mod ever.

 

[TRTLGQ]

Gday Robin,
I have a 2002 4.8 auto and can certainly sympethise with you, I have never crapped my pants like I did on the weekend in the high country. I actually checked twice to see if I was in low range 1st,felt like I was on a slippery dip. The gearing is very bad. But to help you out I have had reduction gears fitted to my previous fourby (GQ) and was extremly happy the gears were by marks adaptors. I will be soon getting reduction gears fitted up to my current ride. As yet dont know what percentage reduction to go for.

 

[tj81]

hang on tight......

 

[4.2BeautUte]

You are just plain not driving it right!

I have driven my 2002 4.8 auto (which is far heavier than standard) in some very hairy clay steep situations and have had more control than in my old manual diesel.

If driving through the brakes is not working you are not doing it right IMHO. I can descend a steep sand dune or steep rutted out clay track with far more control in my auto than I could in my manuals.

Maybe the ABS is interfering (can't see how) but I have no ABS in my 4.8 and I had no ABS in my previous diesel auto (which also kicked ass driving through the brakes).

 

[Robin Miller]

Hi TRT

Glad I'm not the only one - I have decided to go with a set of the mid-range gears 2.88:1 which will give me the same reduction as my manual 4800.
Currently about $1700 fitted.

While this won't address the torque converter issue - I expect to sort that out some other way.

I still need a description of how it works in low range - if you know where their is some info I love to know.

Robin

---------------------------------------------

Gday Robin,
I have a 2002 4.8 auto and can certainly sympethise with you, I have never crapped my pants like I did on the weekend in the high country. I actually checked twice to see if I was in low range 1st,felt like I was on a slippery dip. The gearing is very bad. But to help you out I have had reduction gears fitted to my previous fourby (GQ) and was extremly happy the gears were by marks adaptors. I will be soon getting reduction gears fitted up to my current ride. As yet dont know what percentage reduction to go for.

 

[Robin Miller]

Hi Jeff

Love the pics - I put up a couple in an Exploroz post and at Stockton steep down was no issue but it seems to me that the skill level required is to high to be practical for me on our icy tracks.

I think I can't lose by taking Heiuf's advice as a start.

But I do need to know more about auto's exact operation , to decide if playing with torque converter is on - on it might yet be easier for me to steal injector pulses from the engine instead.

Still looking for info on boxes operation - like simply does it or does it not lock in low.

Robin Miller

 

[davekaren33]

I am no expert. I recently fitted an electric lockup to my auto which I purchased from somewhere in Melbourne. This information I obtained on this site. I use this because I tow a large van and with it switched on it is like driving a manual. I was informed by the gearbox specialist that sells the product it is also usefull when four wheel driving but dont forget to turn it off when slowing down and coming to a stop as it will stall. Perhaps other members who have fitted this may like to make a comment.
David

 

[auggie]

Sorry for changing the subject but Jeff WA where abouts are you in those pictures looks nice.

In my 3l Auto i drive thru the brakes or use a tiny bit of handbrake. Never have any problems? Never had reduction gears myself but i imagine they would be awsome for steep acents and decents.

 

[Robin Miller]

I wish their was a kit for the 5 speed David - but there is great post on this site about a DIY lockup , but it isn't optimized for crawling downhill.

Also no transmission handbrake like on the 3 lt , so your a bit stuffed for ready fixes.

Robin

I am no expert. I recently fitted an electric lockup to my auto which I purchased from somewhere in Melbourne. This information I obtained on this site. I use this because I tow a large van and with it switched on it is like driving a manual. I was informed by the gearbox specialist that sells the product it is also usefull when four wheel driving but dont forget to turn it off when slowing down and coming to a stop as it will stall. Perhaps other members who have fitted this may like to make a comment.
David

 

[4.2BeautUte]

All those places are about 30min drive from my driveway. Between Nannup and Busselton mostly.

 

[Robin Miller]

Well the 2.88:1 reduction gears went in late friday night just in time for a downpour in the hills north of melbourne.

We gave them a good workout and simply put they work.

These gears give my auto 4800 the same reduction in low range as my manual 4800 and certainly give back some significant engine braking. This means that we can still lope along at 40kmh in low range without the engine reving to high.

The cars downhill ability has gone from hopeless to just poor , which I can live with , while we work on other improvements.

The Marks adaptor gears are straight cut and a bit noiser , but not significantly so.
I guess being straight cut they would be more efficent to.

I could only really test on a hill with 25 degre slope and the gearing held the car in 1st but the slope was long enough to get the engine to go much over 3500 rpm so I could not deterimine if the transmission would upchange and run away at higher revs.

 

[LukeGX]

I could only really test on a hill with 25 degre slope and the gearing held the car in 1st but the slope was long enough to get the engine to go much over 3500 rpm so I could not deterimine if the transmission would upchange and run away at higher revs.

In my 3.0l auto there is no engine braking when in Drive but if I pull the shifter down to 1st then it brakes well with the engine (and obviously will not upshift). The difference is quite noticable, it feels more like the transmission is locked.

 

[gregby]

Well the 2.88:1 reduction gears went in late friday night just in time for a downpour in the hills north of melbourne.

We gave them a good workout and simply put they work.

These gears give my auto 4800 the same reduction in low range as my manual 4800 and certainly give back some significant engine braking. This means that we can still lope along at 40kmh in low range without the engine reving to high.

The cars downhill ability has gone from hopeless to just poor , which I can live with , while we work on other improvements.

The Marks adaptor gears are straight cut and a bit noiser , but not significantly so.
I guess being straight cut they would be more efficent to.

I could only really test on a hill with 25 degre slope and the gearing held the car in 1st but the slope was long enough to get the engine to go much over 3500 rpm so I could not deterimine if the transmission would upchange and run away at higher revs.

Hi Robin - long time no speak!

As you may remember, I've had a 4.8 auto since 2003 and I must admit that the downhill engine braking (or lack of) is the only negative I have with the auto. The issue is that you have many slippery slopes in Victoria whereas we have mostly dry country up here in Qld where I drive. Having said that, I have had a few scary moments on slippery rainforest tracks myself. I have become quite adept at driving through the brakes so now it's just normal for me.

I can confirm that the auto (in my 2003 anyway) will NOT up-shift automatically at any revs when in 1st. The engine will just hit the rev limiter.

I've always wanted reduction gears to make the vehicle better in these conditions but have not been able to justify it since we haven't had much rain around Brisbane for many years. It's been a wet few months in October & November though so that might change.

Good to see that you've stuck with the Patrol though. I've been wondering what to do myself with the new 2011/2012 Patrol looking so bloated etc. I've resigned myself to the fact that the GU might be my last "real" 4WD!!. I'd be interested in the economy you are getting from the 2010 auto.
edit: Just saw your post here: http://www.patrol4x4.com/forum/491246-post58.html

Also wondering what you've done about the lack of a sub tank - I assume there's still room for the aftermarket ones though.

edit: Just saw your post here re 75l sub tank http://www.patrol4x4.com/forum/478535-post18.html

I'm still of the opinion that you get a far more drivable vehicle with the petrol auto while having heaps of power for towing etc. Unfortunately (flame suit on ) the 3L auto leaves me wanting for MUCH more power.

You should try Jay's "Power Valve Mod" and also the "Cruise Control in Manual Mode" mod as well (if you haven't already)
http://www.patrol4x4.com/forum/diy-modifications-accessories-40/4-8-cruise-manual-mode-mod-44263/

Cheers
Greg

 

[SpiderM]

I've resigned myself to the fact that the GU might be my last "real" 4WD!!.

Nah mate, that was the GQ, far too many electric gizmo's on the GU and a bit too girly

 

[Robin Miller]

Hi Greg

I remember and the things we have helped each other with over the years.

Mostly post on exploroz as find this format hard to use (this is second time I have typed this).

THanks for that - I needed to know that it won't upchange out of first on me.


I have followed some of the mod threads and they have been helpful espically the manual in cruise mod.

The power valve one made no observable change to my car but fuele use has gone up from 16.4 to 17.5 around town - but my data (2 tanks) is not sufficent to draw conclusions from just yet and I will probably make this mod switchable so I can instantly compare.
I certainly felt that a new auto 4800 was the only way to get a real 4wd with all new bits and I will attempt to solve the autos issues and make it better than the manual 4800 which I will keep.
The auto isn't as fast on the highway though, but takes off better than the manual.
It is thirster around town but I was surprized to get 13.6 on a 1000km recent trip to Stockton - never once got that out of manual.

In the month I have had it I have added the 75lt sub-tank which is a great professional standard kit, a front locker and now the 43% gears.

And its only been back to Nissan on a flat bed truck once at 15 hours old (I claim this record)

Robin Miller

Hi Robin - long time no speak!

As you may remember, I've had a 4.8 auto since 2003 and I must admit that the downhill engine braking (or lack of) is the only negative I have with the auto. The issue is that you have many slippery slopes in Victoria whereas we have mostly dry country up here in Qld where I drive. Having said that, I have had a few scary moments on slippery rainforest tracks myself. I have become quite adept at driving through the brakes so now it's just normal for me.

I can confirm that the auto (in my 2003 anyway) will NOT up-shift automatically at any revs when in 1st. The engine will just hit the rev limiter.

I've always wanted reduction gears to make the vehicle better in these conditions but have not been able to justify it since we haven't had much rain around Brisbane for many years. It's been a wet few months in October & November though so that might change.

Good to see that you've stuck with the Patrol though. I've been wondering what to do myself with the new 2011/2012 Patrol looking so bloated etc. I've resigned myself to the fact that the GU might be my last "real" 4WD!!. I'd be interested in the economy you are getting from the 2010 auto.
edit: Just saw your post here: http://www.patrol4x4.com/forum/491246-post58.html

Also wondering what you've done about the lack of a sub tank - I assume there's still room for the aftermarket ones though.

edit: Just saw your post here re 75l sub tank http://www.patrol4x4.com/forum/478535-post18.html

I'm still of the opinion that you get a far more drivable vehicle with the petrol auto while having heaps of power for towing etc. Unfortunately (flame suit on ) the 3L auto leaves me wanting for MUCH more power.

You should try Jay's "Power Valve Mod" and also the "Cruise Control in Manual Mode" mod as well (if you haven't already)
http://www.patrol4x4.com/forum/diy-modifications-accessories-40/4-8-cruise-manual-mode-mod-44263/

Cheers
Greg