Drivetrain slipping on '00 LX470 when turning the wheel (???)

[bigun66]

Hello all, I'm having a strange drivetrain problem and hope somebody has an idea what's going on.

I have a 2000 LX470 with 69K miles.

A few months ago we noticed that when you really crank the steering wheel (left or right), the car doesn't move when you give it gas. It will sort of "catch" some, but mostly it won't move at all. There are no funny noised or clanking, it just acts like it's in neutral. The problem is the worst when the wheel is completely turned left or right. I called Lexus and we were several months beyond the 6 year powertrain warranty

I just drove the car today and the problem is much worse now. It is still okay going straight, but if the steering wheel is turned much (say 1/2 turn or more) it will slip. If you are parking the car in a parking lot you'd definitely notice it. Otherwise, the transmission seems perfectly fine in the car.

We bought it from auction with 34K a little over 3 years ago. It has seen light duty city and highway miles. AFAIK, it has never had the tranny fluid changed. I checked it tonight (first time) and it actually seems overfilled (checked it hot and it's well above the HOT marker on the dipstick).

I would really like to hear some ideas on what this is, and how much it might cost to fix. I hate taking a car into the shop without having any idea what's wrong.

Thanks in advance for any help.

 

[NMuzj100]

Start by draining some fluid from the transmission and getting the level right. When I purchased my 98 it had the fluid overfilled and it was adversly effecting the shifting. Drained a bit of fluid and it was perfect.

Unfortunately this sounds a a lot more serious. But maybe just the additional effort required to push the car against the turn is holding it back.

Does the engine rev up?
Do the driveshafts turn?
Can you feel vibration in the TC?
Does the "2nd" or "Power" button effect operation?
How about putting the gear shift in 2nd or 1st instead of D?
Have you checked the TC fluid level?
Does reverse work?

 

[e9999]

checking the ATF properly is often a whole sing and dance thing (leave engine on, go through a bunch of gears etc) - forgot about the 100, but check carefully.

As far as the problem that does seem potentially serious and worth looking at right away to avoid potential locking up at speed etc. Sorry, no specific idea besides the obvious. But I would start by putting it up on jacks, in N and have a look at what goes on with the axles.

 

[SWUtah]

From your post I suspect that since you have never checked your transmission fluid that you aren't a big car guy and do it yourself person. I would suggest that you take it to the local Lexus dealership and have them analysis the problem and give you a price quote. Then contack Lexus corp. if the problem is expensive and plead your case of low mileage and just out of warranty and see if they will pay 1/2 on the repair. Good luck and let us know what you find out.

 

[e9999]

and Welcome to the forum too!

 

[bigun66]

Thanks a bunch for the replies.

I will try draining some transmission fluid.

Some excellent questions, I just went out to see what the effect of the power button, and starting from 2nd or 1st rather than D, and I was unable to make it slip AT ALL. The car was cold, and I didn't have time to warm it up.

I rarely drive this car, but it's starting to look like it only happens when the car is warmed up. This would explain why nobody reported it before (we mostly do trips of < 5 miles in this car).

When the slipping happens, it happens equally bad in reverse as it does in D.

I will tell you that the tranny behaves normally in all other respects. It shifts smoothly, goes into OD on the highway. A minor clunk sometimes between D and R but I've heard much worse.

I can't answer the questions about whether the driveshaft is turning, TC vibration & fluid level. Will get a better look at it tonight.

I suspect that since you have never checked your transmission fluid that you aren't a big car guy and do it yourself person.

That's true, especially when it comes to drivetrain. I've never regularly owned/driven a 4WD, this is my wife's car. It will eventually be going in for service, but as I said earlier I don't like to take it in when I don't have a clue what's wrong.

Thanks again for the help, will reply when I find out more.

 

[bigun66]

Thanks a bunch for the replies.

I will try draining some transmission fluid.

Some excellent questions, I just went out to see what the effect of the power button, and starting from 2nd or 1st rather than D, and I was unable to make it slip AT ALL. The car was cold, and I didn't have time to warm it up.

I rarely drive this car, but it's starting to look like it only happens when the car is warmed up. This would explain why nobody reported it before (we mostly do trips of < 5 miles in this car).

When the slipping happens, it happens equally bad in reverse as it does in D.

I will tell you that the tranny behaves normally in all other respects. It shifts smoothly, goes into OD on the highway. A minor clunk sometimes between D and R but I've heard much worse.

I can't answer the questions about whether the driveshaft is turning, TC vibration & fluid level. Will get a better look at it tonight.

I suspect that since you have never checked your transmission fluid that you aren't a big car guy and do it yourself person.

That's true, especially when it comes to drivetrain. I've never regularly owned/driven a 4WD, this is my wife's car. It will eventually be going in for service, but as I said earlier I don't like to take it in when I don't have a clue what's wrong.

Thanks again for the help, will reply when I find out more.

 

[jp213a]

Take your truck to one of the chain auto part stores have them connect their on board diagnostics scanner (OBD-II). This is usually free of charge. The automatic transmission has fault codes just like the engine. If there is a code in memory, they should be able to read it and tell you what it means. If they can't tell you what it means, post it and someone with a factory service manual will. This will at least give you some information before taking it to the stealership. There is also a remote chance the previous own or auctioneer filled it with the wrong fluid.

 

[bigun66]

Well I drove it for 20 miles tonight, tried to reproduce the problem and couldn't. It's hard to believe it's working fine today after slipping so badly yesterday.

Sounds like a good suggestion to hook up the diagnostics equipment. I had no idea the transmission generates fault codes. If I ever figure this out I will post what i find.

 

[uHu]

Just a comment on checking the AT fluid level.
Remember it has to be checked with the engine running.
At least when you have a dipstick. (a -00 should have)

 

[NMuzj100]

Checking the transmission fluid is easy.

1. Park on a level surface
2. Allow the engine to idle in Park or Neutral
3. Check the level (if fluid is too hot to touch with a bare hand use the "hot" scale)
4. Don't add too much fluid - only 1 pint (1/2 quart) between the add and full marks - so add slowly

When the fluid warms it expands (higher fill marks) so the fact that it is only acting up when warm could be a sign that fluid overfill is the problem.

 

[Jim_Chow]

Does anyone know how accurate the drain pan specs in the FSM are? If they're right on, you could just drain the pan and fill with exactly the amount spec'd.

I checked the vol 1 FSM (but for the 5speed A750F tranny). If the vehicle doesn't move forward or backwards, it's not a good sign. It suggests that there is something wrong w/ either the tranny connecting rod, rear planetary gears, pawls, or torque converter clutch. The latter three sound bad. IIRC, the only tranny failures I remember from following this board for about 4 yrs (and there have only been 2-3 cases of which one was aggressively driven by a PO w/ no PM) is on the '00 LX. Check out

https://forum.ih8mud.com/showthread.php?t=8432&highlight=transmission+failure

It would be helpful to new 100 series buyers if we had a list of statistics on failures on this board for stuff like HG's, trannies, manifolds, starters, etc (who had them and at what mileage).

 

[100 TD]

I hate to sound negative , but if it was me, I would pull the pan off NOW, and have a look for metal, burnt clutch material etc. If nothing particular shows up, I would clean the filter, put the pan back on, then do a tranny flush with Toyota tranny fluid or exact spec aftermarket fluid, by flush I mean buy 20 litres of fluid, remove the 2 oil cooler pipes, put the outlet pipe into a 20 litre bucket, with measurements on the inside for each litre in marker pen, start engine and as it pumps out, pour new oil back in the inlet hose at the same rate. You may need assistance to do this and to stop the engine occasionally. This way you flush out most of the "OTHER OIL" (and whatever else was in there) and are back to good oil throught the tranny and see how it goes from there. At least then you know what oil is in there and have flushed out most/if any contaminents were in there. If it starts to happen again, you will need to take it to someone as you may have a sticking solenoid, or something much worse.

 

[LXPearl]

Was the CDL dash light ON when it was acting abnormal?

 

[100 TD]

I thought the same thing as I read the post LXPearl, but as I read the explanation of it not moving in forwards or reverse when you hit the gas, I thought NAH, CDL won't stop it from moving if you HIT the gas, but maybe he's not hitting it enough if the CDL button is engaged! ALso that the tranny was overfull was a concern.
There is also the possibility of not knowing at all about the CDL, and the lamp could of course be blown.

Was the CDL dash light ON when it was acting abnormal?

 

[SWUtah]

There is also the possibility of not knowing at all about the CDL, and the lamp could of course be blown.

That makes sense if the light was blown and they had the CDL engaged it would bind when they turned on dry pavement. I would take it out and drive it hitting the CDL to see if that fixed the problem and if the light is out then take it to the dealer and have it fixed.

 

[wareagle]

I've heard of a similar decription, but diagnosis was not the tranny. Instead, it was the center diff. This is unlikely, but I'll run through a couple of quick checks. Have you recently replaced tires. are all 4 tires same size, make, etc. does problem go away if you lock center diff (don't try turning steering wheel on a harf surface or you'll bind the driveline). Mark

 

[wareagle]

Well, after posting my treo showed the last couple of posts, so it looks like center diff was already suggested. FWIW, The issue I was suggesting was related more to the torque bias I/Os. I was wondering if tires are not same size or speed sensors are failing. Either can royally screw up an AWD system.

For example, I ran into a similar issue with one of my troopers and the B&W "torque on demand" center diff system. In 4 high (biased) I could not backup occasionally in extremely slick, very low speed offroad situations unless my swamper TSLs were at street level PSI. The size differences of 33" swampers at 12PSI seemed to scramble the CPU. With locked center, i never had a problem.

Just a thought.

 

[bigun66]

Thanks all for the continued suggestions. To answer a few questions,

No, I have not recently replaced tires, they are all stock size and properly inflated.

I can virtually guarantee center differential lock was not engaged. Certainly not intentionally. I could try engaging it to see if it fixes the problem, but remember, it works fine in a straight line in all cases. I'd have to find some mud to try that.

The problem I'm having now is getting the problem to reoccur. I rarely drive the car myself, but for the last few days whenever I do drive it, it's working perfectly. My wife and I both noticed the problem several months ago, and it seemed to just go away. It came back again with a vengence on Saturday. It was really bad and actually difficult to move the car in a parking lot. Strange.

FWIW, I suspect it is not the transmission itself. I think the extra tranny fluid should be drained but I doubt that's the culprit.

At this point I plan to take it in to have the tranny error codes checked, and maybe take it to Lexus for a diagnosis/estimate. It's very unlikely I'd have them actually do the repair though. I just want to know what it is first, then explore options. For instance, if it's a 4K repair bill I would consider trading it in.

 

[SWUtah]

Thanks all for the continued suggestions. To answer a few questions,

No, I have not recently replaced tires, they are all stock size and properly inflated.

I can virtually guarantee center differential lock was not engaged. Certainly not intentionally. I could try engaging it to see if it fixes the problem, but remember, it works fine in a straight line in all cases. I'd have to find some mud to try that.

The problem I'm having now is getting the problem to reoccur. I rarely drive the car myself, but for the last few days whenever I do drive it, it's working perfectly. My wife and I both noticed the problem several months ago, and it seemed to just go away. It came back again with a vengence on Saturday. It was really bad and actually difficult to move the car in a parking lot. Strange.

FWIW, I suspect it is not the transmission itself. I think the extra tranny fluid should be drained but I doubt that's the culprit.

At this point I plan to take it in to have the tranny error codes checked, and maybe take it to Lexus for a diagnosis/estimate. It's very unlikely I'd have them actually do the repair though. I just want to know what it is first, then explore options. For instance, if it's a 4K repair bill I would consider trading it in.

good plan, you could do the CDL in the grass, you just need some wheel slip. Please let us know what you findout. Very interesting problem.