Auto 5th Gear Slipping

[Peterpilot Avid PP Poster! Find all posts View Profile Close Peterpilot]

I took the Prado on the sands of Stockton Beach for the first time last week, drove from Anna Bay to the Signa shipwreck and back (about a 3 hour round trip). Whilst on the beach, I noticed the transmission slip a few times when shifting gears. Felt like a box full of neutrals. Once back on the highway, the problem persisted every time the transmission shifted into 5th. I've been driving around with 4th selected to avoid the problem now. This is the first 4wd I've owned that is an auto. I'm yet to talk to Toyota about it, I'll call them tomorrow and keep you all posted. Has anyone else suffered similar?

It's quite disappointing and doesn't give me any confidence in the vehicle as a credible off roader. My previous ride was an 80 series manual and I drove it for 700km over the sand dunes of the Simpson Desert without even a flinch. I drive this Prado 50km on the beach and it limps home...

[D4D Addicted PP Member Find all posts View Profile Close D4D]

Re: Auto 5th Gear Slipping

Beach driving+auto+V6+big right foot = cooked auto trans fluid (would be my guess)

[Peterpilot Avid PP Poster! Find all posts View Profile Close Peterpilot]

Re: Auto 5th Gear Slipping

Beach driving+auto+V6+big right foot = cooked auto trans fluid (would be my guess)

I doubt it but if that's the case, all I can say is better to find out on the beach than in the desert! :wink:

[Peterpilot Avid PP Poster! Find all posts View Profile Close Peterpilot]

Re: Auto 5th Gear Slipping

The fluid was recently replaced by Toyota at last service. I'm wondering if it was replaced with the correct type and/or quantity. These 5 speed autos are a sealed unit and have no dip stick... :roll:

[D4D Addicted PP Member Find all posts View Profile Close D4D]

Re: Auto 5th Gear Slipping

The fluid was recently replaced by Toyota at last service. I'm wondering if it was replaced with the correct type and/or quantity. These 5 speed autos are a sealed unit and have no dip stick... :roll:[/quote]

Why would they replace it? It's meant to last a lifetime, unless your auto spits it's fluid out like mine did the day after delivery :evil:

[Peterpilot Avid PP Poster! Find all posts View Profile Close Peterpilot]

Re: Auto 5th Gear Slipping

Why would they replace it? It's meant to last a lifetime, unless your auto spits it's fluid out like mine did the day after delivery :evil:

Auto fluid does not last a lifetime, nor does brake fluid, coolant and gear oils. They require inspection and replacement as needed. Toyota service intervals are to inspect auto fluid every 40,000km and replace (if necessary) every 80,000km. Manual transmission oil and Transfer oil have similar inspection and replacement schedules, diff oil is inspected every 20,000km and replaced every 40,000km. Toyota also specifies replacement of auto fluid, gear oil, transfer oil and diff oil if the vehicle is used for towing.

Prior to my ownership, at the 120,000km service in January 2008, Toyota made a note on the invoice "AUTOMATIC TRANSMISSION POWER FLUSH SERVICE REQUIRED AT NEXT SERVICE INTERVAL". I mentioned this at the 130,000km service in September 2008 and it was replaced with "ATF TYPE WS 4LITRE".

[Peterpilot Avid PP Poster! Find all posts View Profile Close Peterpilot]

Re: Auto 5th Gear Slipping

I'm off to Toyota now, they want me to bring it in to check the auto fluid level...

[Peterpilot Avid PP Poster! Find all posts View Profile Close Peterpilot]

Re: Auto 5th Gear Slipping

Well, the fluid quantity and quality are both good, so the fluid hasn't been "cooked". Unfortunately this also means it's not as easy as just topping up the fluid level. Toyota couldn't find the fault on their test drive and they want me to bring it back so they can keep it overnight and un some diagnostics when I can afford to let them have it. :x

[siukalo Junior Member Find all posts View Profile Close siukalo]

Re: Auto 5th Gear Slipping

I don't understand this......Why are you driving on the beach on 5th gear? Legal limit is 40k in Stockton. Anyway, when you are driving in sand (following the speed limit) you should be using a lower gear to give you a bit more power to overcome the soft sand. I don't think leave it into D is advisable, as this will put a lot of load into the little gear. How does everyone think on this?

When the trasmission over heats or being worked really hard, either the auto oils loses lubrication which causes a friction between the gears to start rubbing each other, or the bearing cannot cope with the load. Usually, in a senario like this is not the gear that breaks, it is the bearing. When the bearing seize, it starts to grind and the little bits of metal will start to come off the bearing. Ususally those metal flakes will get trap in the tranmission shift gates. You should find the transmission slips really bad during morning, but get better as the temp goes up. (Because heat expands and opens up the shift gates).

Anyway good luck with the repair.......just don't say anything at Toyota about sand n tow......n......

[Peterpilot Avid PP Poster! Find all posts View Profile Close Peterpilot]

Re: Auto 5th Gear Slipping

Thanks siukalo, you raise some interesting points:

I don't understand this......Why are you driving on the beach on 5th gear? Legal limit is 40k in Stockton.

Quite true, 40km/hr is the speed limit and I did for a brief time exceed this speed :shock: I went as fast as 60km/hr and was overtaken by a Suzuki... ops:

Anyway, when you are driving in sand (following the speed limit) you should be using a lower gear to give you a bit more power to overcome the soft sand. I don't think leave it into D is advisable, as this will put a lot of load into the little gear. How does everyone think on this?

I would be interested on other peoples views here too, don't forget I've never owned an auto 4X4 before so this is all new to me. There is nothing I've read to suggest that you need to select a lower gear in sand, only for steep descents as far as I know. I was under the impression that you just left it in D and the transmission is then free to choose the correct ratio. If the sand gets soft, it will downshift without losing momentum. This is my understanding of the advantage of having an auto in sand over a manual. Anyone else have an opinion on this?

When the trasmission over heats or being worked really hard, either the auto oils loses lubrication which causes a friction between the gears to start rubbing each other, or the bearing cannot cope with the load. Usually, in a senario like this is not the gear that breaks, it is the bearing. When the bearing seize, it starts to grind and the little bits of metal will start to come off the bearing. Ususally those metal flakes will get trap in the tranmission shift gates. You should find the transmission slips really bad during morning, but get better as the temp goes up. (Because heat expands and opens up the shift gates).

That's interesting because I haven't been able to reproduce the slipping since, and nor have Toyota. The slipping only occurred when shifting into 5th and only when the transmisson was at temperature, never when cold. :? I suppose draining the oil would reveal if there is any loose metal filings in the oil.

Anyway good luck with the repair.......just don't say anything at Toyota about sand n tow......n......

The car was never towed, and I maintain that you should be able to drive a Prado on the beach without adverse effect. If you can't use a four wheel drive for it's intended and designed purpose, then it's just a poser's car. I'm not interested in a show pony! :wink:

[leachy_9 Advanced Member Find all posts View Profile Close leachy_9]

Re: Auto 5th Gear Slipping

I don't know about differences between the V6, 5 Speed auto and the D4D 5 speed auto. But with the D4D auto it will not select 5th gear when in low range. So if driving in soft sand (soft enough for low range) you should never be in 5th gear, even if 'D" is selected.
If your on sand hard enough to allow hi range and going fast enough for the auto to select 5th gear then I would think that the sand is hard enough not to put undue stress on the transmission.
For what its worth, I nearly always use low range when in sand (unless it's very hard packed) and 95% o the time just leave it in “D”. Only when tackling the toughest sand dunes (Bornholm WA) or steep descents have I found the need to hold the auto back in a lower gear.

Leachy

[George_M Junior Member Find all posts View Profile Close George_M]

Re: Auto 5th Gear Slipping

Hi PP

I had a similar problem with my Prado (auto, petrol) about twelve months ago, except that it seemed to briefly hit neutral when changing up to/through the three higher gears. My local dealer (God bless 'em - they were great!) diagnosed the problem as a "blown clutch cluster" in the auto transmission. Vehicle was off the road for three weeks, but all's good now. Fixed under warranty.

Good luck!

George_M

[Peterpilot Avid PP Poster! Find all posts View Profile Close Peterpilot]

Re: Auto 5th Gear Slipping

Hi PP

I had a similar problem with my Prado (auto, petrol) about twelve months ago, except that it seemed to briefly hit neutral when changing up to/through the three higher gears. My local dealer (God bless 'em - they were great!) diagnosed the problem as a "blown clutch cluster" in the auto transmission. Vehicle was off the road for three weeks, but all's good now. Fixed under warranty.

Good luck!

George_M

Thanks George,

Was this occurring all the time or particularly when the transmission was at temperature? Sounds like the same problem that I'm having, but mine is only when shifting into 5th. Problem is that mine is out of warranty. :shock:

Cheers,
Pete

[George_M Junior Member Find all posts View Profile Close George_M]

Re: Auto 5th Gear Slipping

Hi PP

I had a similar problem with my Prado (auto, petrol) about twelve months ago, except that it seemed to briefly hit neutral when changing up to/through the three higher gears. My local dealer (God bless 'em - they were great!) diagnosed the problem as a "blown clutch cluster" in the auto transmission. Vehicle was off the road for three weeks, but all's good now. Fixed under warranty.

Good luck!

George_M

Thanks George,

Was this occurring all the time or particularly when the transmission was at temperature? Sounds like the same problem that I'm having, but mine is only when shifting into 5th. Problem is that mine is out of warranty. :shock:

Cheers,
Pete

Hi Peter

In my case it started in pretty easy country up behind Bairnsdale, on a cool day. I first noticed that the transmission seemed to briefly hit neutral between 2nd and 3rd. By late afternoon it was effecting 3rd, 4th, & 5th. In the end the transmission would not change up to 4th or 5th. Came home on the back of a flat-bet truck:-(

The dealer was very good....

George

[Bushbasher Out of control poster! Find all posts View Profile Close Bushbasher]

Re: Auto 5th Gear Slipping

Another advantage to driving in 4th or 3rd is that you will have engine braking whenever you lift your right foot off the accelerator. When you lift off in top (4th or 5th dependent on gearbox) you don't get the engine braking, the car simply cruises and gently decellerates.

Using the engine braking on soft sand saves having to use the brakes and helps prevent the tyres digging in as you stop.