[oldschool]

H Guys,

New to the forums as far as posting goes but have gathered much info in the past. Thought I'd post some pics from a forced upgrade last week.
After a couple of hundred km up the beach in 36 deg weather my auto decided it had had enough and cooked, tried to be nice but with a car full and super soft sand it was getting hot at 30k/hr.
So here is a mod I was meaning to do before this trip. Would also be a great mod for anyone towing.

Parts needed, relay, switch and some wire. I used a Narva 68044, and a Narva LED Rocker switch.
I'd expect this can be done on most models using this auto, as long as it has a lock up feature as standard in overdrive.
Its had the thumbs up from an auto mech, its basically what you pay a couple of hundred dollars for as a 'kit'.

Its a very easy mod, just find the Auto control plug on the ECU, Its the orange one. third from the left. Then locate the Yellow and Green wire, its the far right side second wire down.
I cut this and went for a drive to confirm the auto lock up didn't engage and I was right, stayed slippery the whole time.

Then I put the relay so in its normal state the ECU still controls the Lock up, when the switch is on, it activates the relay and sends 12v to the Auto.
Done. The switch fits nicely in the centre console.

I'll post some pics when I can.

[GeckoXL7]

Thats some thinking i like

I read it did engage in low range, but having a switch for it is a good idea.

[oldschool]

Mine definitely doesn't engage in low range, works exactly the same in 4L as High. Slips in every gear until at a certain throttle pressure and a certain speed in OD. That's why my Auto fried. Half throttle in 3rd Low range for half an hour on sand and it was done.
But now it engages in 2nd third and OD, at the flick of a switch, H4 or low4. Mine doesn't stay locked in first as you come to a halt. so it doesn't stall. seems to loose Hydraulic pressure. But, my auto is still cooked and free runs in 1st and slips badly in reverse, So it may just be mine that it does this.
I'll have a new auto in it in the next few weeks so I'll report back then. It should in theory lock in first as well to help in down hill descents.

[Chop]

Do you have a decent cooler fitted? And did the auto have good service history? That is the key to preventing a premature death of an auto. You really shouldnt let them go any longer than 20,000km max on service intervals and even less if towing.

[oldschool]

Yep, its had a perfect history, it has a water cooler in the radiator and I'd also fitted a 11 row aftermarket cooler as well, though that would be enough, but not so, just got way to hot.
But this lock out switch is the only real solution long term, and for towing.

[Chop]

oldschool wrote:

Yep, its had a perfect history, it has a water cooler in the radiator and I'd also fitted a 11 row aftermarket cooler as well, though that would be enough, but not so, just got way to hot.
But this lock out switch is the only real solution long term, and for towing.

Not necessarily, I've been towing with mine for 4 years on a daily basis. I tow my tools around with it during the week, and have had some big trips in hot weather in the outback and n.t. and mines survived thus far. The auto place i get mine serviced has only commented on the colour of my oil on the first time i had it done there just after i got it.
He said it was a bit dark and likely left to long.

[Bulldog 61]

Heat and water are two biggest killers of auto's, fit the largest external cooler you can, bypass the radiator cooler, fit extened breathers and keep the services up to them.

[oldschool]

Quote:

Not necessarily, I've been towing with mine for 4 years on a daily basis. I tow my tools around with it during the week, and have had some big trips in hot weather in the outback and n.t. and mines survived thus far. The auto place i get mine serviced has only commented on the colour of my oil on the first time i had it done there just after i got it.
He said it was a bit dark and likely left to long.

I think you'll find towing much better being able to lock up the convertor in third as well though. Like have an extra gear!

I will bypass the radiator cooler now too though. Might use that for a hot shower heater!

[got_bar_work]

My auto guy says its a very bad idea to bypass the radiator.
The fuild can get to cold and a small air cooler cant dump heat spikes fast enough where the water in the radiator can absorb them and slowly get rid of the heat.

[ChrisN]

I've been running a large external ATF cooler in my GQ for a couple of years now, with the radiator bypassed completely. The auto box does run cool on the road, but no problems are evident as yet in gearbox behavior or the appearance of the ATF at servicing. It's something to keep in mind if the gearbox misbehaves, but I don't think it's as much of a problem as many suggest.

Oldschool - here's something you might like. Some folks on the Patrol4x4 forum have done a lot of work on the manual lockup switch for the torque converter.



With this circuit the momentary contact switch will lock the TC, and a tap of the brakes will unlock it. Read the full thread http://www.patrol4x4.com/forum/nissan-patrol-gu-gr-10/patrol-auto-converter-lock-up-11914/.

There have been some further developments of this circuit, but this version works very well for me. It works a treat at keeping the gearbox temperatures under control (confirmed by a VDO temp gauge on the gearbox).

Cheers!

[Gwagensteve]

Note subsequent to ChrisN's post - patrol guys are obsessed with converter locks, mostly, in my opinion, because they aren't ever geared properly for offroad work. This shouldn't be a problem for suzuki owners. Nissan autos also seem to be able to take high loads on their lock solenoids. I'mont sure this is the case for a vitara, and it would suck to be the guy who finds out they can't.

Got_Bar_Work - I don't believe your auto guy.

a) The hot side of my auto frequently runs cooler than the bottom tank of my radiator. I don't want my cooler to be heating up my auto. Under any circumstances
b) If a "small" air cooler can't dump heat spikes it's too small. Thats a new one for me. trans shops do use the "overcooling" line a lot, which is also nonsense in Australia.

It has nothing to with how "slowly" the radiator cooler can get rid of the heat. A liquid to liquid cooler is very efficient, but can only cool the trans fluid to something above the temperature of the cooling medium - in this case something above the temperature of the bottom tank of the radiator. Yuk.

As for the benefits of manually locking the converter, I'm not sure this is a good idea. There is good reason the factory doesn't lock the converter under high load - the solenoid that locks the converter isn't rated for high load. Newer autos are designed to lockup in all gears but use much more sophisticated control software and are designed to deal with the load. I would DEFINITELY avoid locking the converter whilst towing*

Personally, it sounds to me like you weren't driving to the conditions, you'd retained the transmission "heater" the factory installs, and your additional cooler was too small. How were you determining how hot the auto was getting? How hot does it run under normal conditions? Was the engine temperature gauge running hotter than normal? What tyre pressure were you running?

AW-4 failures are very rare, There's usually a good reason why the fail, and it's generally not due to the inadequacy of the cooler in an otherwise stock car.

*Most manufacturers advise against towing in overdrive, and therefore against towing with the converter locked. Whilst the lack of slip will help to reduce heat, there's a byproduct - no torque multiplication. By towing in third, (direct) engine revs are higher, throttle opening is smaller, so load is reduced, and the converter slip is multiplying torque. factory cooling takes this into account.

[fordem]

Gwagensteve wrote:

As for the benefits of manually locking the converter, I'm not sure this is a good idea. There is good reason the factory doesn't lock the converter under high load - the solenoid that locks the converter isn't rated for high load. Newer autos are designed to lockup in all gears but use much more sophisticated control software and are designed to deal with the load. I would DEFINITELY avoid locking the converter whilst towing*

<SNIP>

*Most manufacturers advise against towing in overdrive, and therefore against towing with the converter locked. Whilst the lack of slip will help to reduce heat, there's a byproduct - no torque multiplication. By towing in third, (direct) engine revs are higher, throttle opening is smaller, so load is reduced, and the converter slip is multiplying torque. factory cooling takes this into account.

Just thought I would mention it - on AW4 equipped Mitsubishis, disabling OD will allow the torque converter to lock in third, I have personally tested this - I believe this is also the case on AW4 (03-72LE) equipped Suzukis and maybe standard practice with the AW4

[jdk81]

Did some testing

My aw4 03-72le does lock the torque converter in 3rd when overdrive is turned off.
When in overdrive (overdrive on)
3rd does not lock
And in OD it locks the torque converter at light to middle throttle, under load it allows torque slip, until it kicks down to 3rd.
Under very light load to no load it unlocks to coast as you would expect.

If lots of headwind and/or uphill it requires more throttle, I let the TC slip for a while, but i instinctively just press the OD off, and maintain same revs etc.
I used to do the same with the baleno auto under similar conditions.

When towing if load is mid to low I use OD, as soon as i notice any extra load (headwind, hill etc) i press OD off.

i love the OD button

Between 1, 2, D and the OD button there is ample control.
Over riding the locking TC system seems like its not needed for the 03-72le

[Gwagensteve]

That's interesting jdk. I've never felt mine lock in 3rd with the O/D off, I suspect because mines low enough geared I can't really drive on road without using O/D, and in low range there's so little load I wouldn't be able to tell.

It does imply though that it's wise to lock out overdrive if the car can't easily hold it, which, my guess, is what the owner's manual says.

Steve.

[jdk81]

Drive home with more testing, i noticed some extra info.
With OD button off (in 3rd) increasing throttle, it unlocks and raises revs about 250 rpm, then accelerates until it locks the tc again.
It does this in OD too, but much easier to get 3rd to lock.
if big hill and lots of torque slip, obviously 2nd or 1st would be required.

But it definitely seems like the TC is locked in 3rd with OD off, as it feels like a manual of same ratio etc

G16b aw4 (03-72le), 4.16 xfer, 4.875 diffs, 33" tyres

EDIT: Corrected the rpm (from 500 to 250), after more testing.

[oldschool]

Thanks for everyone's input. Some varied opinions for sure, Well further to these comments, the patrol circuit is good but I don't like the way it unlocks when you press the brake pedal, no good for crawling downhill, and obviously I wasn't driving to the conditions, had tyre pressures at 12 psi, tide coming in could only reach about 20-30kmh and 180 km in super soft sand over two days. the added oil cooler was from a clubsport so I assumed would be added cooling. It got hot and it doesn't lock in third with the OD off, the new one might though, (actually it will because i've got a cool switch) any way it's done 300k and the new auto has only done 95k so it's going in regardless. Enough ramble, I've got a gearbox to swap.

[Gwagensteve]

OK, some more context.

300K is pretty high for an auto - I'm sure it was well past its best.

I disgree in relation to the brake override. if you need to brake, you don't want the auto fighting the brakes until you (almost) stop, especially if the car is properly geared. You dip the clutch when braking to a stop with a manual, yes? I rarely use 1st gear when descending offroad - it's too low, 2nd is normally plenty. I don't run a converter lock - proof that with the right gearing there's no need for brakes or a lockup converter.

Auto transmissions need a temperature gauge if you drive offroad. Every car, every auto.

[atari4x4]

12psi is where you went wrong...

[oldschool]

atari4x4 wrote:

12psi is where you went wrong...

How so? Tried at 18, 14 then 12 was the best rolling on the sand on the day. Couldn't go any lower.
Everyone's an expert.

[Gwagensteve]

Which "expert" said you couldnt go lower.

[atari4x4]

90% of my offroad experience is sand, I learnt to drive in the dunes years prior to ever having a licence... i might have the experience but i'm no expert though.

12psi is a good starting point & don't be afraid to go lower. starting at 10psi & dropping down to 8psi, you've dropped 20% of you tyre pressure. that gain is massive & it will be the difference between cooking your auto & generally working the car hard @ 12psi & barely breaking the surface and walking every where @ 8 or 10psi.

i've lost count of how many sand virgins i've lead into the dunes, never had a vehicle with me that's been doing it hard after dialing in the tyre pressures. straight off the bat, after doing 4hrs of highway driving, i'll dump mine down to 10psi HOT, in the morning they're usually around 8 or 9 psi COLD, i'll head out, get the tyres up to temp & check them again & burp them if required.

never had a problem, never will... my trans temp gauge proves that & with 6-8psi in my camper trailer i just need to ensure i have enough momentum to get over a dune so i don't have to worry about reversing down.

FYI getting bogged doesn't happen in suzuki's .

[oldschool]

Thanks, I wouldn't have normally got that low with a full load.

[GeckoXL7]

oldschool wrote:

atari4x4 wrote:

12psi is where you went wrong...

How so? Tried at 18, 14 then 12 was the best rolling on the sand on the day. Couldn't go any lower.
Everyone's an expert.

When it comes to XL-7s everyone is a expert on here

The first trip done in the XL-7 was in dunes out of PT Augusta on the original bridge stones did it on 18psi floated over everything, but that was dry somewhat compacted sand , over the 9 years have lowered pressures more and more, eg Beach port down to 14psi and even down to 9 along the water which made a massive difference as it was wet turned up sand prob from the other suzuki owners who traveled it before me just floated over it, and thats with full car and recovery crap in the back. but the rear end at thoughs pressures makes me feel uneasy (floats around) so i just take it easy.

previous to the XL-7 i had a jimny for 4 years and well there is a massive difference on sand, lighter, shorter and more clearance, low pressures isnt a issue, with the xl-7 you have the issue of the long wheel base, chassy rails draging in the sand and also the rear diff if go to low. Larger tires have helped in that regard.

I found 13psi to be the sweet spot on soft boggy sand i usually can stop and start and crawl around quite slow eg walking pace at that pressure, but at times you do need to drop it lower, or burn out the clutch / or transmision.

[atari4x4]

^^^ don't listen to that turkey... i've seen him knee deep in struggle in the sand, read some of his other waffle if you want proof.

oldschool wrote:

Thanks, I wouldn't have normally got that low with a full load.

full load, like a week long camping trip loaded?


FYI tyre pressure isn't vehicle specific, it's about having the right pressures for the terrain you're in.

EDIT:

oldschool wrote:

Thanks, I wouldn't have normally got that low with a full load.

i've taken the valves out of a solid axle hilux & basically made him drive into the ocean first to enable him to be able to drive out. the ocean was already at his wheels & by this stage & i'm not talking about those nice flat beaches in QLD, you can't fuck with the Southern Ocean & expect to win.

[got_bar_work]

My stock lwb vit on 235 sucked at 12psi on Stockton
I had to run 9psi before it would stop digging in everywhere.
I ran my coily at 5psi

[Marko_SJ]

I'd love to bring my Sierra down Souff to try real sand.

Don't have any real dunes up here.

[Gwagensteve]

So, it looks like, in summary:

The auto had 300,000km on it- that's quite a lot
Nobody actually knows if heat killed it or it was actually just worn out and couldn't hold gears under high load because of clutch wear
We don't know how hot it got because it didn't have a gauge or how much hotter it was running than during normal use
The owner didn't manually gear it down to reduce load therefore allowing it to lock in 3rd (apparently)
The owner might not have done enough to mitigate load on the car (tyre pressure too high)


So I'm not sure, from this data, it's not at all clear that the manual converter lock would have made any difference. If the auto was sufficiently worn that it was struggling to hold a gear with the higher than normal load of the sand, then the auto would have cooked regardless of whether the converter was locked or not. Once the revs are above the converter stall speed (around 2500 rpm from memory) slip should be very limited - circa 150rpm or so - so the heat generated by converter slip will be minimal.

In my opinion, manual converter locks are an interesting widget - kind of like a line lock or a rear disconnect - fun to play with, but it's not really changing the world.

Steve.

[oldschool]

I'd have to go with heat killing it. Although no temp gauge the last fluid change was a month ago. And it went from new red to black water, the additional cooler had changed colour and flaked some paint. It was stupidly hot! Anyway I'll be using the lock up as an added feature and will be installing a temp gauge. Ill post some data next time on the sand.

[fordem]

Curiosity question here - does Suzuki not have an auto transmission overtemp indicator?

The AW4/03-72LE has provision for a temperature sensor, which Mitsubishi uses - the TCM will indicate an overtemp condition, on my car, a flashing neutral light (depending on the flash rate) indicates either an overtemp condition or the presence of an active TCM failure code.

[atari4x4]

I don't think it does in the SV's... I'll have a suss of the FSM