# driveshaft check help



## Bvogt (Dec 19, 2021)

Yea, I know…it’s me again abusing all of your knowledge and expertise (always good to start with a little ass kissing. So, last month I bought a second 14 CDT with 106k on it and at some point it had front end damage/“repair”. I have driven it 1k now and am going through it now. Oil/trans fluid, def heater, intercooler pipes (when they arrive). Struts and shock blow (Bilsteins in the future).

anyway, tomorrow I am replacing both front wheel bearings. While I have them off, is there a shade tree way to determine the "intermediate driveshaft" has been bent or anything? It does have a noticeable vibration when going around 70mph. This could be attributed to crap tires and worn wheel bearings. I imagine there is a chance that something could have damaged one of them. With the wheel bearing off I will have better access to it. Anything to look for or do? Thanks again.


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## snowwy66 (Nov 5, 2017)

Lift one side up and drive the car. The free tire will spin. If you don't see anything try the other side. 

One tire needs to be still so that only one tire spins. So check one side at a time.

Watch the axles. If they're bent. You'll see it in the spin.


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## Bvogt (Dec 19, 2021)

snowwy66 said:


> Lift one side up and drive the car. The free tire will spin. If you don't see anything try the other side.
> 
> One tire needs to be still so that only one tire spins. So check one side at a time.
> 
> Watch the axles. If they're bent. You'll see it in the spin.


copy that, like an old limited slip RWD car. same idea?


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## snowwy66 (Nov 5, 2017)

Yep


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## 15cruzediesel (Sep 30, 2019)

Bvogt said:


> Yea, I know…it’s me again abusing all of your knowledge and expertise (always good to start with a little ass kissing. So, last month I bought a second 14 CDT with 106k on it and at some point it had front end damage/“repair”. I have driven it 1k now and am going through it now. Oil/trans fluid, def heater, intercooler pipes (when they arrive). Struts and shock blow (Bilsteins in the future).
> 
> anyway, tomorrow I am replacing both front wheel bearings. While I have them off, is there a shade tree way to determine the "intermediate driveshaft" has been bent or anything? It does have a noticeable vibration when going around 70mph. This could be attributed to crap tires and worn wheel bearings. I imagine there is a chance that something could have damaged one of them. With the wheel bearing off I will have better access to it. Anything to look for or do? Thanks again.


First thing I would do is rotate the tires and see if anything changes in regards to the specific 70 mph vibration on a specific road test/course.

If it does most likely tires/balance/bent rim. Meaning the only thing not changed is the axle shaft and bearings.

If not then replace the bearings since your doing that anyway, and retest. Preferably on the same road under the same conditions. Might involve swapping the tires back to their original locations for a 4 wheel comparison.

If the condition persists than it might be in the shaft itself. I m guessing not very likely but if it was in wreck all bets are off.

Typically drive train vibrations will show up going up hill under load.


Out of curiosity how did you determine it had bad wheel bearings?

BTW be extremely careful if you plan on having one wheel on the ground and the other off the ground under power, spinning it at high revolutions to see if something is bent. Sometimes you have to ask yourself what could possibly go wrong here or am I about to hurt myself.


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## Bvogt (Dec 19, 2021)

15cruzediesel said:


> First thing I would do is rotate the tires and see if anything changes in regards to the specific 70 mph vibration on a specific road test/course.
> 
> If it does most likely tires/balance/bent rim. Meaning the only thing not changed is the axle shaft and bearings.
> 
> ...


Oh yes, not the safest thing to do. Farm boy in me doesn’t fret too much…probably why I’ve been hurt so many times lol…ugh.

anyway, I want to address everything up front now before it becomes a bigger issue down the road. Looking at some of the shoddy work they did putting easy things back together, it’s enough to give me pause. Bearings: no hum, no slop when jacked up, but 107k on a car that was in a wreck that I have no details on…worth just doing it for peace of mind. Planned tires and wheels, and struts. If the shaft needs to be replaced, so be it, they’re not making these anymore, barely sold many and parts are getting discontinued left and right.

might as well swap things out before all of you do 🤪. Thanks a lot for the input guys!


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## 15cruzediesel (Sep 30, 2019)

Bvogt said:


> Oh yes, not the safest thing to do. Farm boy in me doesn’t fret too much…probably why I’ve been hurt so many times lol…ugh.
> 
> anyway, I want to address everything up front now before it becomes a bigger issue down the road. Looking at some of the shoddy work they did putting easy things back together, it’s enough to give me pause. Bearings: no hum, no slop when jacked up, but 107k on a car that was in a wreck that I have no details on…worth just doing it for peace of mind. Planned tires and wheels, and struts. If the shaft needs to be replaced, so be it, they’re not making these anymore, barely sold many and parts are getting discontinued left and right.
> 
> might as well swap things out before all of you do 🤪. Thanks a lot for the input guys!


You might be surprised how many of these cars are wrecked and used parts available.

Just have to search....


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## Bvogt (Dec 19, 2021)

Bvogt said:


> Oh yes, not the safest thing to do. Farm boy in me doesn’t fret too much…probably why I’ve been hurt so many times lol…ugh.
> 
> anyway, I want to address everything up front now before it becomes a bigger issue down the road. Looking at some of the shoddy work they did putting easy things back together, it’s enough to give me pause. Bearings: no hum, no slop when jacked up, but 107k on a car that was in a wreck that I have no details on…worth just doing it for peace of mind. Planned tires and wheels, and struts. If the shaft needs to be replaced, so be it, they’re not making these anymore, barely sold many and parts are getting discontinued left and right.
> 
> might as well swap things out before all of you do 🤪. Thanks a lot for the input guys!


Yea, so did the bearings, no biggie. They didn’t look bad. Tossed wheels from my other CDT. Seems to be good to go.

I didn’t feel any slop in the driveshafts, but drivers side trans seal is leaking…so that’s awesome 😒. Project for next weekend. Anything to be wary about doing it, never have? Is the seal protector necessary during install and removal?


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