Drivetrain Lash
 

It seems that my 2003.5 Protege5 has developed some really bad drivetrain lash. Acceleration is fine, but it is virtually impossible to maintain a constant speed - *especially* when going down hill (with the clutch out) - without constantly feeling jerks as the engine and transmission bump against each other. Kind of like when you over-drive first gear and come off the gas - jerk, jerk, jerk... Very annoying.

Is this a common problem? Or can I hope that something is actually wrong with the car that I can have fixed? I love the car, but this is a symptom that, if un-fixable, may lead to me getting a different car.

Thanks,

EJT

yes..it is very common...stock motor mounts are pretty weak....you can get some Mazdaspeed Mounts or AWR Poly Mounts...another option is filling your stockers with some 3M Window Weld...this has been a poor mans trick for quite a while and works VERY good for cheap.

i kinda get the same feeling cruising at 50mph in 4th...it's not "bad"...it's VERY subtle...but it's there...kinda like a weird hesitation in the tranny...my rpm's are stable...but it's like a split-second loss of power several times in a row...freaky.

I've got about 21,000 miles on my 2003 P5 now, without ever having experienced the engine mount problem. How many miles do you guys have on your cars?

I notice it the most in first gear accel, then deceling for speed bumps etc... BTW I have 6k miles on mine, I really notice it at the autocross's, where it feels like bad axle hop and motor mount can can all wraped up into one...

I've got just under 10K on my odometer - and come to think of it I was thinking that under hard acceleration I was feeling wheel hop. I guess it is another manifestation of the motor mounts.

A couple of follow-up questions to my original question:

1.) A search on motor mounts has indicated that I need only replace the front and rear mounts to help (solve?) this problem. Is this correct?
2.) I assume the Mazdaspeed mounts are an acceptable choice (I'd like to stay under warrantee. Who knows what claims Mazda would through out if you messed with something as integral as a motor mount?)
3.) How much of a compromise in engine noise/vibration will I experience. I'm about willing to trade anything to get a better cruising condition, but I don't want to trade one problem for another...
4.) If I have Mazda do the work - how much can I expect to pay (assuming I've got it right with #1)?

Thanks again!

EJT

do yourself a favor and NEVER have a dealership service department do your work for you. EVER.

Also, if you're worried about your warranty, DO NOT EVER MODIFY YOUR VEHICLE. Don't listen to what anyone else says...this is in stone from the Lord himself. trust me.

The vibration isn't bad at all. I just got in the front mount and I LOVE IT!! Best investment I've made so far. The vibration is there and noticably worse when the AC is on but I'm willing to compromise.

Stick with the AWR mounts...they actually do something. I owned a MSP and it wobbled and was as loose as the other stock mounts.

i went though that front one pretty quick , less than 10,000 miles i put in the awr and it feels like a new car

Well, I bought the AWR front mount and 15 minutes later its in the car. Very easy install job.

My thoughts: Wow! :eek: Does the car buck when starting the engine! Otherwise the drivetrain lash is about gone. Well, not gone, but certainly tolerable. There is some vibration through the seat and steering wheel when idling - not bad, but certainly noticable. I haven't tried the wife test yet. I suspect she'll notice and comment.

I'm not sure the mount will stay. The starting issue is pretty big to me. I might try getting the Mazda Speed mount or doing the window-weld trick to the original mount just as an experiment.

BTW, for those who haven't looked, the stock mount is more air than bushing - very soft. I can move the element by hand. By contrast, the AWR mount is rock hard, with a solid bushing.

Thanks for the replies - if/when I try the other mounts, I'll post again.

EJT