driveline still shakes

[slytherin]

I made a big booboo when installing my3550 i forgot to mark the drive shaft, I have turned it 90degrees twice and it still shakes(60 mph it starts and progressively gets worse).I don't think another turn is going to make a difference. also I was wondering since I lowered the car if that had anything to do with it. I need a guaranteed fix is an aluminum drive shaft the answer

 

[VoODoo5Oh]

i have a 3550 with an aluminum shaft and it still vibrates...i plan to buy the d/s spacer from steeda to see if it helps even thought i have a feeling it wont

 

[slytherin]

I have the d/s spacer, came with the kit from d&d, also came to find out one of my wheels might be bent/out of round I'm not sure if it could transmit that much vibration. thanks for the input

 

[VoODoo5Oh]

try to find a shop that has a Hunter Road Force Variation balance machine.....that will deterine how bent your rim is ....sometimes you can even match the tire to the rim to elimanate that vibration...

 

[slytherin]

thanks for the input, I was thinking on just buying new 98 cobra wheels since my 95's are not in that good of shape apearence wise as well as one of them being jacked up

 

[VoODoo5Oh]

sounds good....good luck

 

[cb18201]

arnt the gears in your tranny different from stock to make your car faster or have more torque? with your 4.10s that could deffinatly do it, its the drive shaft tryingto spin so dam fast but just is almost falling out of momentum. i have heard that having 4.10s an a tremec makes your car feel like you have 4.30s. does the car vibrate and make a humming type noise and when you really go faster the shifter shakes and rattles?

 

[5.0 from 95]

My aluminum DS fixed all my shacks in the a$$ end. I did not change out the transmission though. I have heard this is the fix most times when there is shacks back there.


Paul

 

[slytherin]

CB you are exactly right the 1st & 2nd gears are alittle less than a T5, up to 50mph there is nothing felt then it comes in around 60 and progressively/aggressively gets worse around 100mph your saying your hail mary's it feels like the car is going to come apart ive done the jack the car up just enough to clear a2x4 and spin the wheels to see which one will kick out the 2x4 to no avail, a friend has the alumDS im gonna try to talk him into letting me borrow it b4 i make that investment, ive read shimming at the tranny mount might help since the 3550 sits lower than a T5. thanks for the input it is greatly appreciated

 

[VoODoo5Oh]

shimming the tranny mount at which mounting location?(trans or x-member?)
and how do you know how much to really shim? thanks

 

[SexyStang1994]

shimming the tranny mount at which mounting location?(trans or x-member?)
and how do you know how much to really shim? thanks

Get the car on a flat surface... set it down preferable on two sets of ramps so the suspension is fully loaded. Remove the driveshaft. Place an angle finder where the DS bolts up to the rear. Then, take the same reading from where the slip yoke of the DS goes into the transmission, OR you can measure at the harmonic balancer.

If the two angles added together come out to 0... then its all good. Otherwise... start shimming. I would shim at the transmission mount. Find an Energy Suspension mount, they are a bit taller than stock unless the preload plate isnt used and teh bumps arent shaved down.

Link: http://www.baselinesuspensions.com/info/pinionangle.htm

Check out there Tech Glossary too... interesting stuff in there.

 

[VoODoo5Oh]

thank you for the info

 

[Stump1000]

Check your exhaust and make sure it isnt touching or almost touching the car anywhere. My h pipe used to be about a 16th of an inch from my crossmember and it would hit and feel like vibration sometimes.

 

[VoODoo5Oh]

ill check that...thanks

 

[Badlilstang]

I went through all this.. the spacer didnt do crap and I have an alluminum driveshaft and a tremec TKO. The only thing that fixed my problem was I took my car to a shop that does a lot of suspension work and had them set my pinion angle.. after that it went away.. then I broke a tranny.. put in a new tranny and it came back!!!!

 

[slytherin]

thanks for the input and the diagrams, the car goes to the shop on weds, I'd rather have a pro fix it the first time than me guessing and wasting good weather. thanks again

 

[VoODoo5Oh]

slytherin: please let us know what they say....thanks
badlilstang that sucks.....whas breaking the tranny a result of setting the pinion angle or just a bad trans?
are any of you guys running a energy suspension trans mount? i am...and i wonder if that is just the nature of that type of mount?

 

[Badlilstang]

Im guessing something in the pinion angle changed and im not sure why. I woulndt recommend an energy suspension bushing on an SN95 car.. I ran one and got some vibes from it.. and Ive had 2 freinds with SN95 cars use them and take them right off.. my fox never had a problem but if you look at a fox crossmember it has bushings on the ends of it where as the SN95 is a solid type mount on each end.

 

[SexyStang1994]

I have noticed hardly any extra vibration with the Energy Mount. Then again, like in my T/A i didnt use the preload plate and I shaved down the bumps on the mount.

 

[Badlilstang]

I have noticed hardly any extra vibration with the Energy Mount. Then again, like in my T/A i didnt use the preload plate and I shaved down the bumps on the mount.

I bet not using the preload plate helped.. and shaving the bumps down may have helped also.. ill recommend that next time someone tries one of those mounts.