avmedco

Problem: Until the engine warms up fully I have a slight whine/whirring noise and minor vibration at center console. Only occurs when stopped and in drive. In Park or neutral and stopped, no noise. Goes away under acceration. Once car is warmed up no more noise. Also minor delay in the initial shift out of first. After shifting once or twice out of first it shifts normally, warmed up or not. Also noticed a very slight ticking noise from passenger side lower dash area when slowing to a stop. This almost sounds like a leaf fluttering in a vent.

1998 Sc400 86k miles. Last ATF Type IV change ~15k miles ago. Fluid level and color check OK.

Any ideas?? Thanks in advance!

jibbby

Mine did the same and then went out....Had to rebuild....Then again mine is older and was beating it regularly with nos shots....Yours should not go out...Try sythetic tranny fluid change, look for adjustments, and or bad tranny code reads....I would have an experienced import tranny shop have a look at it....

I would check the tranny mounts and engine mounts as well....Vibration occures when the rubber mounts start to wear out....

np20412

......I always thought that the delayed shift out of first with the VERY cold engine was NORMAL. Mine does it everytime. Your car will also not drop into 4th gear when the engine is cold, it will hold it in 3rd even at 45mph.

As for that noise, check your lugnuts. If they are loose, you will hear that exact kind of noise at low speeds when slowing down.

avmedco

Reading the threads on vibration and noise of this type I decided to starting with the easiest fix, and it WORKED.

Swapped out the transmission mount (looked perfectly good whether installed or removed) with new mount.

No more noise or vibration! Still slow to come out of 1st when cold but it sounds like this is more indicative of the design than with a maintenance issue. I can live with this as this whole thing cost me $55 vs thousands for a trans rebuild or new drive shaft and the headache of multiple diagnostic visits to a repair shop.

Thanks to everyone who takes the time to post this very valuable info.

98LexSc400

So you replaced a good transmission mount? Did I understand you right. Just checking because I have a 98 SC400 with same miles on it wondering if I need to cehck or change? I looked at it last time I changed the fluid. I removed the crossmember and the mount moved around easily but it had no signs of breakage or seperation actually it only had what looked like paint chips flaking off it.

Blu92SC4

Does your O/D light blink on your dash? You may have a No. 2 Solenoid problem like I have where tranny shifting is affected

O. L. T.

iTrader: (17)

Delayed shift when cold is because your tranny fluid is not completely filling your Torque Convertor until after the first shift. It's quite natural.

The fluid is cold and dense, the TC is only half full. After the shift it fills up.

Koma

iTrader: (3)

On a side note, you shouldn't really be driving your car until it is fully warmed up. The oil inside isn't warmed up enough yet, when the oil is warmed up more it expands. You wouldn't want to spin up an engine when it's not fully lubricated.

Sly Guy Yu

Hey dude, i got a 98 sc400 with 33,000 miles. In the morning (or when the car is completely cold) It has a hesitation getting outta 1st or 2nd. I think it's second, but i cant be sure. as for vibrations and stuff i dont get that.

Sly Guy Yu

shouldnt the engine be fully lubed like 30 seconds after start up? The engine usually revs around 1000-2000 rpms, and i keep my rpms under 2000 when i drive to school, until fully warmed, i doubt that is a problem, but i dont know the 1uz motor that well, any input?