Ok this is something new to me. I've just recently bought a Verada (KF) and noticed that occasionally at highway speed there's a somewhat alarming shudder. At first I thought it was just the road, but it happens on perfectly smooth roads. It's happened a few times now and it seems to start off with a few very small jolts, then stops for a couple seconds then becomes a full shudder for anywhere up to 2 seconds. similiar to running over rumble strips. It goes away on its own, or if I give it some throttle.
I don't seem to really notice it in the steering wheel, but at the same time it feels like the shake is originating from the left side of the car, but I could be mistaken as i've not been a passenger in the car with it happen.
The car has no noticeable problems other than a very slight 'stumble/shake' at idle which seems to be fairly normal for these 3.5L engines?

Reading up on generic 'shuddering' problems on google it seems this could be related to the torque converter? :eek2: but that to me would seem like it would show up with a lot of shaking in the wheel since its a front wheel drive car?
Is there any easy way to try and fix this myself?

The only prob with torque converters that I've found was one with a balance issue.
And like a wheel out of balance it only occurs in a small rpm range.
In that case it happened at about 1200rpm.

Are you sure it's not a HT prob, like a plug or HT lead?
Dizzy cap or rotor?
Does it happen on hills?

Sounds like damper clutch in the trans, when was the last time you had a trans service?

Cheers Dave

Hi guys

I can and will look over the service logs later. I only recently purchased the car (less than 500km ago) and the owners seemed meticulous with the maintenance and upkeep of the vehicle. It looks like its been cleaned, polished and waxed every week religiously. It only seems to happen at highway speed (80kph+) and judging by the low KM I doubt the previous owner had it at highway speed very much. It's possible they never knew about it as a pre-existing condition, or it's somehow only developed just after I bought it. All fluids and maintenance have been done by the book. I noticed the manual doesn't mention anything about changing the ATF fluid unless towing and its never had a towbar

It happens both on hills and on flat ground. It's not a regular occurance, I can be doing a constant rpm and speed and it will not occur at all, or it may come up occasionally out of the blue with no change in speed or engine rpm

Pull the tranny dipstick and tell us the colour of the oil. It should be pinky red.

Also with it being intermittent, I would be looking electrical.

Ok this is something new to me. I've just recently bought a Verada (KF) and noticed that occasionally at highway speed there's a somewhat alarming shudder. At first I thought it was just the road, but it happens on perfectly smooth roads. It's happened a few times now and it seems to start off with a few very small jolts, then stops for a couple seconds then becomes a full shudder for anywhere up to 2 seconds. similiar to running over rumble strips. It goes away on its own, or if I give it some throttle.
I don't seem to really notice it in the steering wheel, but at the same time it feels like the shake is originating from the left side of the car, but I could be mistaken as i've not been a passenger in the car with it happen.
The car has no noticeable problems other than a very slight 'stumble/shake' at idle which seems to be fairly normal for these 3.5L engines?

Reading up on generic 'shuddering' problems on google it seems this could be related to the torque converter? :eek2: but that to me would seem like it would show up with a lot of shaking in the wheel since its a front wheel drive car?
Is there any easy way to try and fix this myself?

Won't feel it in steering

Flush trans and add a tube of shudder stop

Ok guys I pulled the tranny dipstick and errr... yeah that could be the problem. I know what ATF normally looks like (purple/red) and this is brown. Even my much older car's trans fluid still looks red. So i'll be changing that
Aside from that the engine bay is near spotless, crazy clean for a 15 year old car :D

I've never had to change ATF fluid before, What's the procedure in the verada's? Is there a drain plug or do I need to jack it up and remove the entire pan. And is there any particular type of ATF to get or is it all much the same?
And finally should I still add shudder stop or try new fluid first and see how it goes?

edit: Read the service manual for a 'KH' verada. Assuming the process is the same I need to disconnect a hose underneath the vehicle and fluid will pour out from there when the engine is started, then remove a drain screw. refill and repeat a couple times to get the correct level and unsure most of the old fluid is flushed. It mentions replacing the filter but doesn't mention 'where' the filter is?

Interesting that everyone has homed in on the gearbox as being the cause of the shudder, when it could be a lot of other things!
How many Km actually on the car?

By all means fix the dirty ATF problem - get a FLUSH done by a pro shop or a Mitsu dealer, just dropping the fluid and putting in any old ATF won't do, it needs to be the proper Mitsu fluid, and it needs to be flushed to move all the old oil out of the torque converter.

Get back to us if you get the fluid changed if the shudder is still there afterwards.

As for "crazy clean" engine bay, be suspicious of this, it may be hiding leaky rocker cover seals - see how it goes though. I bought a TL from a car yard, I assumed the "crazy clean" engine bay was a good sign, but within 1,000 km there was oil leaking from both rocker covers. Not something you pick up on a test drive.

150,000km on it

Whats a typical cost of fluid flush? Things around here tend to be more expensive, but want to make sure i'm pretty close to the mark

the crazy clean engine bay seems to fit the crazy clean interior and exterior. I checked everywhere and it really is crazy clean. Even run my fingers in hard to reach spots and its schmick. So at this point in time i'm not suspicious of foul play

http://www.mitsfix.com/FixedPriceServices.html

$185

I've never done a DIY flush, but the method you outlined sounds like it would work. Going to use a fair bit of Mitsu ATF though.

Filter, it you have one, is a cannister type screwed to the top of the gearbox, under the air ducting. Looks like an ordinary oil filter. Some boxes have them but it was deleted off later boxes.

Run your finger along the joint between the rocker cover and the cylinder head on both banks. If you come up with oil on your finger the rocker cover seals are oozing oil. An easy check. Also lift one of the front bank spark plug connectors, if it has oil on it at the top the spark plug tube seals are leaking. Also an easy check and an early indication of work that needs doing on the engine.

(My TL, also "crazy clean" from the car yard detailing, had both rocker cover gaskets and tube seals leaking at 136,000 km.)

Check your Throttle Position Sensor, it seems odd but I was having issues like you describe (car would shudder randomly when using the throttle to maintain speed (60, 80, and possibly 100 I think)). It would also drop revs very briefly, as if someone quickly turned the key off and back on again.

Turns out the TPS was out of alignment (my fault, I put another throttle body on the car and didn't check it). Mine has white out on the the screws and the metal so you can line them up for a quick adjustment, yours may or may not have this. (properly do it in the future is reccomended, by checking continuity between two pins and moving the TPS).

EDIT: actually yours sounds more sinister, mine was more like a vibration that would disappear if I accelerated harder or let off completely.