Transmission slipping? - Benzworld.org

washington dc ML · 08-15-2005, 12:58 PM

My transmission on my 99 ML430 seems to slip into gear under hard acceleration. Normal day to day driving and rush hour traffic I have no problems, but when I try to "gun it" it seems to just sit, then slide into gear. The engine makes noise like it's moving and the RPM rise but other than that it seems like I'm not picking up speed as fast as I should.

Has anyone had this problem?

LOCHS 2 · 08-15-2005, 04:13 PM

Quote:

washington dc ML - 8/15/2005 1:58 PM

My transmission on my 99 ML430 seems to slip into gear under hard acceleration. Normal day to day driving and rush hour traffic I have no problems, but when I try to "gun it" it seems to just sit, then slide into gear. The engine makes noise like it's moving and the RPM rise but other than that it seems like I'm not picking up speed as fast as I should.

Has anyone had this problem?

but not for a while now. The engine revs up and there is this hesitation as if the ML is trying to decide which gear to go in to and once it makes it's decision all those RPMs are kickin' and so it will take off and you can feel the rush--except for me there wasn't any hard jerking of the trans once it engages in the gear of choice. I found this happened when I was on an incline and/or the road was really rough so the MLs "shoes" did not have stable footing. It's hard to actually make it happen (I tried to repeat it so I could share with the dealer but was not able to make it happen when I wanted to). If it happens very frequently then there might be an issue but I can not advise what that issue is--since I don't know. Anyone else?

J-bird · 08-15-2005, 04:30 PM

Not sure this will help, but it might.

http://www.mbnz.org/forums/forums/th...osts=21&fid=29

washington dc ML · 08-15-2005, 04:53 PM

Thanks fellas.

J-bird, what did you enter when you did your search? My right brain(I'm a lefty) thought pattern just can't find the correct phrase for search engines sometimes.

Quote:

J-bird - 8/15/2005 6:30 PM

Not sure this will help, but it might.

http://www.mbnz.org/forums/forums/th...osts=21&fid=29

[:)][:)]

J-bird · 08-15-2005, 04:56 PM

for transmission when I looked at the archives. Good luck! :)

AC_ML · 08-15-2005, 06:21 PM

When you say "gun it", are you meaning pushing the accelerator until you feel the click of the push botton at the end of the accelerator...?

If so something may be wrong.. You may want to get a service transmission oil stick and measure your transmission oil. Remember that you need to get a new cap since the transmission cap is not reusable.

ML 320 engines transmission design are notorious for slipping when you accelerate (cars or SUV's). They just rev up until 3000 or 4000+ RPM and then the gear kicks in. Unless you push the accelerator until it clicks the button at the end of the accelerator, which when pushed, it should immediately shift down gears for quick response.

I haven't hear any people complain about this on any engine above the 350, though..

Good luck...

AC

Andrew2004az · 08-15-2005, 06:45 PM

I have the same thing happen to me. but it only happens when you gun it and your car needs to downshift 2 gears. our 5spd autos cant skip a gear so it must engage the gear below then go down another. but instead of giving you power the rpms go up slightly untill the gear is fully engaged. lets say your going 40mph in 5th gear and you floor it downshifting to 4th gear wont give you great acceleration so your cars going to want to put it in 3rd but the car must first go to 4th then 3rd during the 5-3 gear transition your rpms rise since no gear is fully engaged and the rpm must rise to be able to shift into a lower gear. just like if your driving a manual transmission if your in 5th gear and downshift to 3rd your rpms will rise. basically what i think our car is trying to do is what a manual driver does called rev matching or some call it blipping the throttle. the new 7speed mercedes transmission fixes this by allowing the transmission to skip gears while downshifting.

washington dc ML · 08-16-2005, 05:41 AM

That's one thing I don't really care for in this vehicle is that red do not touch cap under the hood.

I'll try to schedule a tranny drain and refill ASAP, with my luck the transmission will fail dead in the middle of winter. [:)]

washington dc ML · 08-16-2005, 05:42 AM

I'll keep that in mind. I'm carpooling this week so I have make time to drive using the recommendations you guys have offered.

Quote:

Andrew2004az - 8/15/2005 8:45 PM

I have the same thing happen to me. but it only happens when you gun it and your car needs to downshift 2 gears. our 5spd autos cant skip a gear so it must engage the gear below then go down another. but instead of giving you power the rpms go up slightly untill the gear is fully engaged. lets say your going 40mph in 5th gear and you floor it downshifting to 4th gear wont give you great acceleration so your cars going to want to put it in 3rd but the car must first go to 4th then 3rd during the 5-3 gear transition your rpms rise since no gear is fully engaged and the rpm must rise to be able to shift into a lower gear. just like if your driving a manual transmission if your in 5th gear and downshift to 3rd your rpms will rise. basically what i think our car is trying to do is what a manual driver does called rev matching or some call it blipping the throttle. the new 7speed mercedes transmission fixes this by allowing the transmission to skip gears while downshifting.

Andrew2004az · 08-16-2005, 03:56 PM

both of our ML's do the same thing 00ml 320 and 02ml 320. so i know its not related to certian years or cars. i think the c230 loaner car did the samething also.