Jerking In Tranny When Gearing Down

[hammo400]

Hi,

It's been many months since my last LS 400 confession - I have a 98 with 80K, dealer serviced religiously at 15K, 30K, 60K. I started MOBIL 1 SAE 5W30 Full synthetic when I purchased in Oct. 2004. Oil / filter change every 2K. I'm getting a full tranny flush next week, and problem may go away - fingers crossed.

Anyway, here it is:

I've read all the stories of the gear-engage-jerk, but my problem is different.

I experience a 'jerking' motion MOST OBVIOUSLY in stop/go highway traffic driving at low speeds (>20 MPH to 0 MPH) as I come to a stop. It's like when the auto trans gears up from 2 to 1, I get a jerk, then come to a stop. ANNOYING. No smooth slow-down here! Problem happens when warmed up , not as obvious when cold. Happens when slowing from any speed ,and jerks just before stopping.

Took it to LEXUS, had a test drive with a mechanic but of course it didn't happen in parking lot, and there was no commuter traffic to test in.

I purchased an extended GOLD warranty at time of purchase for $1500.00 that goes to 100K or 2 years. Well worth the $. I'm hoping if the flush doesn't work it's the Torque converter or links - both of which are covered.

WHAT ELSE COULD CAUSE THE JERK / SHUDDER JUST BEFORE STOPPING ??????

Thanks . This Forum is great for tips.

HAMMO400

[nc211]

I have heard of several of these complaints. A friend has a 98 as well, took it to dealer a few times, still does it. My 95 does it as well. I think it's a characteristic of the car to be honest. The tranny FLUSH might help. Their is a difference between a flush and a drain/refill. Flush get's all fluids out, drain and fill only gets like 2 quarts out. I think it's just the nature of the tranny in these cars.

[hammo400]

I have heard of several of these complaints. A friend has a 98 as well, took it to dealer a few times, still does it. My 95 does it as well. I think it's a characteristic of the car to be honest. The tranny FLUSH might help. Their is a difference between a flush and a drain/refill. Flush get's all fluids out, drain and fill only gets like 2 quarts out. I think it's just the nature of the tranny in these cars.

←

I really hope this isn't the case. One of the astounding features of the Lexus is the Toyota engine and drivetrain. For this jerkingto be a "characteristic " of the car would be a sin ! Not even crappy old fords do this !

I'm hoping the FULL flush will ease it somewhat. They'll be charging me $144.00 to machine flush purge and replace 12 (?) quarts of Toyota Type IV ATF. I'm going to add Prolong as well to the tranny. I swear by this stuff for friction/heat reduction in the crankcase as it bonds to metal at molecular level and has NO solids in suspension (graphite etc.).

If there is a 'problem' can anyone suggest a source that I can replace under warranty??

With the drive I have everyday to work, this 'jerking' will drive me insane !!!

[GRAND_LS 4]

I USED to have jerking when downshifting, until I drained and refilled the tranny a few times. I used to notice that if i had the PWR mode ON, the jerking would go away. Good luck.

[nc211]

Not to go against the grain, but I would really think about that prolong stuff in there. I put it in my 99 suby outback, and my 01' maxima se, it messed them both up. Smoothed out the shifts for a while, but then it made them really smack into gears later on, almost made it too smooth, like it killed the needed resistance. Just my 2 cents worth amigo. I won't use that stuff anymore.

[SRK]

Yep - stick with Toyota Type IV fluid only - don't dope the trans at all.

[nc211]

I was thinking over the weekend about this for some odd reason. I remember on my Maxima, around 40k miles, the transmission would give off a squeek noise when shifting from 1-2 and 2-3. It was that prolong stuff. It sounded exactly like a fan belt squeek, but was the transmission. If you do decide to put that stuff in there, make sure you compensate the total volume of fluid you're putting in there...i.e., if prolong is 12 oz, then withhold 12oz of toyota fluid. You never want to over-fill tranny fluid. It can burn out the bands by putting too much pressure in the gear box.

[glenmore]

I can't imagine a jerky tranny as typical. The transmission is different in your car versus Gen I, but my 1990 LS400 tranny is still smooth as silk at 140k and one of the true joys of this car. If you are under an extended warranty why put something other than Toyota fluid in there? Gives them the excuse not to honor the warranty.

glenmore

1990 LS400

1991 300CE

2000 C280

[nc211]

Glen, how do you like the 300CE? That is one of my favorite MB cars of all time! I want one so badly.

[glenmore]

nc211,

I love the looks of the car, but then coupes almost always look great! I actually enjoy driving the Lexus more because nicer radio, ac/heater and the PO put some big lo-profile tires on it so it actually handles pretty good. Ride on the Lexus is softer. The 300CE has the original size tires, kinda dinky versus nowadays. The ac and radio are absolutely primitive compared to the Lexus. The ride is a typical heavy and firm MB ride. The inline 6 is smooth but sluggish because of the weight of the car, but once you get moving it is OK. With the AC on it is a downright doggy. Both cars have awesome smooth brakes and trannies. I use the OEM MB brake pads so you get the typical blackened front wheels. The Lexus wheels stay pretty clean. I just put on some euro lights which really look nice on the car. I keep pretty meticulous expense records and after having the car exactly 3 years, and driven miles 111k to 132k, I've spent about $1800 on fluids and DIY parts. With DIY, I've done mostly simple things, tumbler, tie rods, front and rear pads and rotors, eurolights ($330!). At the indie, I've spent about $3000 on tires (350), head gasket (1700) and water pump (700). With the new head gasket I should be good for another 150k. In comparison, I've had the Lexus for 1 1/2 years and driven miles 129k to 139k and I've spent only about $150 in maintenance. The Lexus AC just went on the fritz and I've checked all the PO records and see that the AC has been untouched since new. I just bought a plain Jane 2000 Mercedes C280. It is a VERY nice car. I wouldn't get another w124 unless I wanted a car to tinker with. The technology is getting too old.

glenmore

1990 LS400

1991 300CE

2000 C280