Fern

My '99 Rx300 w/ AWD (139,000 km (86,000 miles) has started a strange clunking shortly after I changed the fluid (T-IV) 4 litres (drain and fill)

The fluid has been drained and filled twice over the last 60,000 km w/ T-IV.

When I shift from Drive to Reverse I get a clunking.

Manual says a drain and fill is 3.9L I used 4 litres and still get a clunk.

This occurs mainly in my driveway with a slight incline.

Any ideas???

Just changed the plugs to NGK iridium, don't know if this is also contributing to the jerk/clunk when shifting from R to D or D to R

Any ideas:
engine mounts?
trani mounts?

Tammy

Does the dipstick indicate the transmission is at the full level mark, and not over filled?

toy4two

sounds like you over filled it.

TunedRX300

Pop the hood and have someone to watch the engine as you shift. If the engine is rolling around shifting from R to D, most likely engine mount are worn. The easiest one to exam is the dogbone one on the passenger side.

salimshah

Is it P -> R

or R -> N

or N -> D

Please use search to find my post on how to check tran fluid level.

P -> R jerk on incline is normal. On incline engage the parking brake before moving the lever to P and then shut the engine off. Similarly after starting the engine, put the trans in R/D before releasing the parking brake.

Salim

Fern

The dipstick appears to indicate overfilled. When hot and in park and idling the dipstick shows above the HOT mark closer to the between the work "type" and "T-IV"

I also did not drain the front differential as suggested by other members... Could this be contributing to problem.

I started by filling 3.4L, and the clunk was really noticeable (almost like metal hitting metal) and when I increased to 3.9L it appears to have gotten smoother. I then just emptied the fluid in the forth bottle for a total of 4L.

It does the jerking/ clunking from D to R and P to R and a bit from R to D all mostly on incline...

Are there any DIY to inspecting mounts.

Thanks guys,
As you can see my response is at 3:30am as it really seams to be bothering me. Vehilce had all the service history done prior to my purchase and I was hoping on having it for some time. Its just this darn jerking /clunking issue.

I remember when I had the last trani drain and fill done at Lexus dealer (about 30,000km ago, the lexus tech told me manual says 4L but he put in a bit more since it shifted better.

I have also heard other members saying a bit more than manual also makes for slightly better shifts... Now others saying beware of overfilling???

Help

My 1st SUV

Lots of complaints on trani for 1999 Lexus RX 300 on the USA Lexus forum.

http://us.lexusownersclub.com/forums...howtopic=28020

Fern

Thanks for the input, but I wouldn't consider that helpful... Need some suggestions on correcting problem instead.

I refuse to consider trani is going, vehicle has been babied since new.

Lexmex

I hear that clunk from D to R, too. Been hearing it for a long time.

salimshah

I am paraphrasing in simple terms, so the techies need to give me some latitude ..

There are solonoid driven brakes, in the transmission which lock certain gears from spinning and allow the "right" gear to engage.

Only in N the wheels are freely connected (drive/spin). When you are on incline the gravity pull creates a turning force through your wheels to the tranmission and the counter is provided by the brake action on the gears. This prevents your vehicle from rolling when parked on incline. On the other hand the brakes dig in to prevent motion. ... sort of like a stuck cog. When eventually you want to move the brake are released but the stuck cog like phenomena (sp?) does not allow free movement till a jerk sets it free.

Note: One can eliminate or reduce the tension on the transmission by using parking brakes .. specially on an incline.

Fluid level: I can only suggest fill to max level and not beyond. I am sure there is margin and tolerance issues, but the lube and power-transfer action are acheived safely at that point and below till min.
All moving parts generally dont like to sit in a tub of lube as frothing can happen and proper flow is interupted and there will be a problem with temprature. [folks with better understanding can shed more light .. my knowledge is limited].

Salim

Fern

to all those who responded THANKYOU,

I called 2 lexus service depots today and spoke with techs regarding the drain and fill level.

They both said a simple drain and fill on rx300 w/awd should not get more than 4L of T-IV including the front differential which fills via dipstick.

I am going by local Toyota dealer tonight on way home from work and buying another 4L of T-IV to drain and fill, only differnce is this time, I'm draining the front differential plug also

See Lexmex's pic showing the front diff and trani drain plugs

salimshah

Instead of drain (specificly partial drain) you can opt for suction out of the dip stick hole. If you over suck it out, add fresh trans fluid instead of re-using.

To check level, it is preferred that the RX is driven till normal opertaing temp is acheived. Park on level surface and rove your gear shift from Park down to the low gears and bring it back. Stop at each position for 5sec or so. With the engine running [idle] and the gearshift in Park, check the fluid level (hot marking).

Salim

Fern

Hi Salimsah,
thanks for the additional input, I have thought of the extraction via tipstick method, I have a topsider oil extractor which I use on my other car since the filter is accessible in the engine compartment, but due the the sensitivity of the trani internals, I did not want to introduce anything foreign that could cause damage.

I am not going to drain and fill the trani again just yet.

I had a talk with the Master Technician at a local Toyota dealership (this guy has won awards for being one of the top techs in Canada) and he said slight overfilling of trani would not be giving me the symptoms I have.

He did not want to speculate on cause (said it would be unprofessional) When I asked about engine mounts, he said no probable since not an early wear item. Especially not the dogbone one on the passenger side.

He asked that I bring in the vehilcle.
Vehicle is scheduled for test run with Master Tech on Tuesday Sept 12/06

Stay tuned for results
I'm not a mechanic but can't help but think this is something driveline related, ie: driveshaft bushings, cv joints, u-joints etc...???

Fern

Just curious but,

when I recently replaced my sparkplugs, I accidentally lost my 10mm ratchet peice behind the engine when doing the middle rear plug. I never did recover it under the car, and thought nothing of it since I suspected it would roll off the trani housing eventually.

The Mrs. has been driving the car and now I notice the trani engagement from D to R or R to D is rough. much like a neutral drop...

Question:

Could the 10mm ratchet peice have fallen somewhere behind engine and in such a position that it could occasionally cause a cable when shifting gears to bind, resulting in this "neutral drop effect" ???

I hope some of the more experience members could comment on what happens to linkages or cables when shifting through the gears from D to R or P to D, etc..

Any possible spots something this small could have fallen to cause this problem?
I'm curious for suggestions as I don't want to wait until Tuesday to have car on hoist.

Tammy

May I suggest removing the right front wheel and inspecting the sub frame and steering rack for your 10mm socket. This allows you to see behind and below the engine.

Go to your local tools outlet or auto parts for a telescopic magnet, if you need.

A good flashlight or drop light is also convenient.

The transmission shift cable enters the transmission just behind the radiator, left of center on the transmission. About two feet from the spark plugs.