ok I have had one nightmare after another. Anyways here goes....

My front plate diff broke on my evo 7. and during that time i broke the right rear cv axle (i have no idea how). So anyways the car made loud popping noises after this happened, and had alot of vibration under load. Anyways I had a new x-fer case built by Map, and my new axle is a new OEM one from mitsubishi. Now "most" of the vibration is gone. However it certainly still has it. Its pretty bad. I have been underneath the car, and the driveshaft bushings seem normal, the rear diff seems good, and i dont see or shake anything abnormal, as well as the tires were all balanced 500 miles ago.

-It "appears" to be RPM related, and seems to vibrate in any gear and its just under load only.
-It is noticeable at 2k and continues to 8k and gets progressively worse as RPM's go up. The whole car shakes.
-I also think my clutch is on its way out, as it does make slight noise under engagement (like the plates are ground down to the rivet etc) and sometimes i have issues with getting into gear.
- what concerns me is perhaps the transmission was damaged when my x-fer case went out? DId i get a bad shaft out of mitsu? I am kinda leaning against the clutch as it didnt do this before the xfer case went out? thoughts? opinions?

 

alignment at of wack? hub assembly going bad? could be a lot of things. do you feel the vibration in the steering wheel?

 

front wheel bearings have been replaced, and it has been recently aligned. no the whole car shakes as i posted above. based on the fact the vibration is driven by rpm, and on-load and considering my recent failures in my drivetrain should be related to that? after all its not driven by road speed so it should rule out unbalanced wheels, alignment
or wheel bearings from my understanding.

 

with this all stated...i'm guessing you dropped your driveshaft?? did you just bolt it back up without proper torque specs? this will cause horrible vibration underload!!

 

check balance shaft belt and timing belt

 

as I said... it only does it under load. Will not do it free-reving. So definately not timing/balance shaft belt. Definately drivetrain related.

 

did you properly torque the driveshaft, this could cause vibration throughout the drivetrain if not torqued properly

 

I know you have replaced one axle already but please check the others as well. A friend of mines had a vibration under load and after the driveshaft and bushings checked out fine he decided to replace the axles and the vibration disappeared. Mind you his axles were not physically damaged in any way but it just turned out to be bad axles that caused a weird vibration onlyunder load.

 

ya i was kinda thinking that as well. Not to mention you can get bad axles with defects in them. i have had that before. definitely something in my drivetrain.

 

Since i got quite a few responses of shotgun things to check timing belt/balance shaft belts etc which have absolutely no bearing on the problem. This is either caused from lack of knowledge or interpreting the symptoms incorrectly....so anyways i have decided to take this in another direction....

Given the symptoms, which part is it most likely to be and why?


-transmission
-new Best Mode transfer case
-clutch
-rear diff
-axles front or rear

 

I say ignition - maybe some bad plug wires.

 

Yeah I'm still leaning more towards something in the drivetrain like the axles since like you said there could be a defect or if they go bad it's the only other thing I can think of that would cause a vibration under load.

 

Since you appear so knowledgeable regarding the prob maybe this thread might help

http://www.lancerregister.com/showthread.php?t=421382

 

your first problem is linking to that forum to someone who prolly knows less than you.... Your second problem is the guy in that thread and you don't understand the difference in when to differentiate when a vibration is happening. Understand if the balance shaft, and timing belt are off, the car will do it at idle, and free revving, as well as on load. If you understand the basics of troubleshooting you would understand this.

 

yup. front right axle went bad...inner knuckle joint/cage went bad. thanks for your help.