Ask The Expert- Lift height/drive shafts

[timp]

At what lift height do I need to think about replacing factory drive shafts?

 

[mecmar44]

The consensus is not so much related to lift height but how much axle droop you are able to achieve. The problem is the front driveshaft will contact the exhaust & crossmember at full droop. The Rzeppa joint also has its own set of limitations when it comes to flex.

 

[timp]

When you say axle droop, are you talking about during flexing?

 

[timp]

I’m only considering min 2.5-3.5 max lift with 35s. Will there be enough droop to warrant new/longer shafts?

 

[Jeep Monkey]

What year JK do you have. the newer models ('12-'18) have a different, more challenging exhaust set up. if you have an older model JK the lift height you want SHOULD be OK. but do not take any one persons "yay or nay" as gospel. Try jacking the frame up to the max height you would want and see what hits or doesn't hit.

Personally i have a 2.5" which totals me at about 3.25" suspension lift. i have no issues but i would not go any higher with mine. 2008 JK

 

[russebp]

After installing the MC 2.5” Game-Changer, my front Rzeppa CV lasted about 7,000 miles (and a few trail days) before the boot broke and slung out the grease. I swapped the CV for the Teraflex Rzeppa pictured ($120). It’s been on a few thousand miles and a long day of wheeling. It’s looking good, but if it goes too soon, I’m swapping the front driveshaft. The rear driveshaft has two CVs. Its boots are still looking good.

 

[timp]

‘16

 

[mecmar44]

When you say axle droop, are you talking about during flexing?

Yes, you'll need to flex the front end so that the passenger tire is stuffed in the wheel well and then check your clearances.

 

[Pthorpe84]

typically a jeep that is 2012 or newer will require a front drive shaft with 3" of lift or greater. This is due to the exhaust contacting the boot on the factory shaft. You can get exhaust spacers, however that is just prolonging the inevitable. Everyone above is correct about the amount of droop you have. (ie how far down the axle can go when cycling the suspension.) There are numerous drive shaft manufacturers and depending on what you do with your rig will dictate what size to get. My opinion is if you get the jeep lifted, get new drive shafts. Its not that much overall and will save you from being stranded someday.

 

[Pthorpe84]

When you say axle droop, are you talking about during flexing?

have a local shop put your jeep on the lift and raise up. Make sure they are picking your jeep up from the frame not the wheels. Check to see if your drive line touches the exhaust crossover. If it does, add a limit strap, exhaust spacers, or a new driveshaft.

 

[GaryG]

I have a 2016 JKUR and had a 3-1/2" gamechanger and exhaust spacers. The front shaft would hit the exhaust at full droop. You could hear the splines thrumming if we were moving and the boot soon wore through. It didn't fail but I wouldn't want to run that way for too long.