the 8 that refuses to get fixed..

Dear all!

i really need your to solve 2 things which i think should be very simple; but both will simply just not get fixed. and its getting worse everytime i take my car to a mechanic.

So i have just moved to Dubai, a land where i think noone is a proper mechaninc. Anyone handed tools is called a mechanic here... so hence my desperate need for your help; because no one is able to give me a proper reason why my car is cursed with vibrations.

so, it all started with a propellershaft vibration: 1st mechaninc spotted that the Centre Mount was faulty (26 12 1 226 662) so we changed it; vibrations still there; so we went and changed the Universal Joint (26 11 1 229 583) and the vibrations went down Considerably; butthey are still there. these are vibrations that happen only when u put pressure on the driveshaft (i.e press the gas) and they are extremely strong when the car goes from a stand still to 60 and much less when u apply pressure on the highway (to take over a car for example)

However; during the process of fixing my driveshaft i have started having another sort of vibrations steering wheel vibrations!!!
these vibrations started appearing only when that same mechanic told me my rubber mounting rods needed to be replaced (31 12 1 136 607). wanting whats best for my car (because i am not dumb; i actually felt the car needed some tightening in the front axle) i said sure; they replaced them and suddenly at around 80 kph my steering wheel started shaking slightly. having had the wheels alligned not long before fixing that step i assumed it was because of the mounting rods. because of work i had to live through it until the day i couldnt handle my vibrator 8 anymore (last monday); so i went to a new mechanic.

I asked the new mechanic to change the brake pads, discs and sensors and to check the reason why the car is vibrating at 80kph; they tell me its the same mounting rods that need to be changed (31 12 1 136 607) i said ok and lets go with it.
i finaly get the car yesterday night; first few trial were fantastic! the car felt tight; steering wheel was lighter, the car felt like it was ready to take on the world (despite the never ending propeller shaft vibrations) then after a few trials of stopping the car quickly; i go on the highway to get home; and this is where i think i had one of my biggest scares: took the 8 up to 90 kph then i applied a SLIGHT touch of break and the car started shaking like never before. the shaking was soo strong that even the cd player started skipping; and my face turned completely white.

to be honest i do not know if the shaking is related to the brakes or if it happens alone at 80.

the car behaves like a dream under 80 kph but totally differently above that which doesnt allow me to provide a proper logical reason to explain..

took it back to the mechanic they said that everything was fitted correctly and they didnt know what was the reason. as they are closed on fridays i asked to have the car back and ill bring it back on saturday.

could anyone please try to reason with me as to why this is happening? i really would like to get rid of the vibrations as my car is my dream car and my daily driver.

i would like to go back at the mechanic tomorrow with a few possibilities to double check on as i really dont think they are as qualified as you but they seem to be the most qualified here!

here are a few of my reasonings:
- is it possible that the vibrations of the propeller shaft is due to the fact that the mechanic stalled it incorrectly? i read somewhere here that the propeller shaft had 27 different positions to be installed; is it possible that the mechanic didnt install it as the factory did and thus the vibrations occur?
- as i have a steptronic gear i tried pushing the car at different gears and the propeller shaft vibrations do not seem to be affected; is it safe to assume it isnt the gearbox?
- concerning the steering wheel vibrations: i know how it feels when wheels are not aligned and your steering wheel starts shaking above 80; but the steering wheel jitters i am experiencing are TOO strong to be wheel related; am i right to think this way?
- should i ask to uninstall everything and pre-load the front axle? as in tighten things when the car is on the ground? i read abt this procedure somewhere in the forums but i am not sure i understand it correctly, if this is the reason can someone please explain it to me?

thank you very much guys, im losing trust in everyone that touches the car here so im really ready for anything; let me know if someone would like to have a skype conversation to really get to the bottom of this; because i really believe that if i dont go with a solution tomorrow i am going to come back home with the same problems. your help is extremely appreciated!

Dear All,

Thank you for your constant support! you are all an amazing bunch! i wish there was more of you here in the area!

Dear Reinhard, thank you for keeping and maintaining such interest in my problems. what happened after the post you mentioned was me going to every single wheel alignment shop i could find and asking if they could align my prop shaft. i kid you not, people looked at me as if i was an alien asking for the moon... so i do not know if my solution is to keep on checking different wheel alignment shops or if it is to find someone patient enough to try to fit my diff in the 27 different positions in order to get rid of these vibrations.. have u heard of any places here in Dubai?

Unfortunately it is Tony Edward Motors that was my first mechanic, the one that didnt fix the prop shaft correctly as well as the bushes.. it seems they have lost interest in me after my problems wouldnt get fixed as i once dropped the car for a week there and they didnt touch it.. im now trying MaxGarage which has been amazingly appraised. you would even be surprised to see the cars they have there!

i am suspecting my shocks for various reasons; once the car started shaking from 0 to 120 kph non stop; until the day i drove it at a 60 kph (the only level of vibration that made me feel the wheels where not going to fall off) for a while and suddenly i hear the car "fart" and the steering vibrations suddenly disappeared!
is it possible that this same shock has manifested itself to only shake at speeds above 80 kphs?
if so do you have any advice on what to do? replace them? all four? any recommendations? (i want to try to keep the car as close to essence it was designed to be, but i do not mind upgrading elements that clearly improve the usability of the car..)

Reinhard, your input is EXTREMELY appreciated; im gonna make sure to print all of your comments and go armed with them tomorrow thanks again!

Feras

ok,

So i went back to the mechanic, explained all the different theories that you have all contributed and they checked everything. they took off all the things they fixed and replaced them again (while carefully preloading the car and tightening everything when the car was on its wheels) and we went for another test drive.

unfortunately the vibrations are still there, but they were not as frequent as before. this means that sometimes the car would vibrate uncontrolably over 80 kph (as soon as i lightly touched the brakes) and sometimes the car would behave completely normally.

they checked the shocks and they seemed to be fine; not great but fine; meaning i should change them sometimes soon but i would rather change them all at once; any recommendations everybody?

following that second test drive; i was told that my tires needed to be changed and my wheels aligned as there is nothing they can do anymore.

would you guys really think that old tires could really make the car shake so much? or was i politely asked to take my problems elsewhere?

Timm, i have the standard "ninja stars" alloys, but i do know that they are very slightly bent; do you think that could be a source of vibration? (although way before all these problems, it didnt seem like they were causing any)

Thanks again guys!