check the rear ujoints and upper rear tri link as well, mine ( ujoints) were toast at 50,000 miles, no play in them but all dried up and rusted solid almost, I'm over 3 inches of lift ( have been for over 100,000 miles) and no driveline problems ever except for the ujoints mentioned above

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MUDD'S MOTORSPORT'S We do IFS lift installs ,
03 OVERLAND EDITION /Kilby-Skidrow-Mopar-4XGuard skids/ 2.5 inch TOTAL CONTROL JBA coilovers -JBA Arms/MOABS-31 FALKEN WILDPEAK AT3W / 4.10's etc, 04 Kilimanjaro Edition loaded, plus 05 KJ limited

Did you replace the u joints with OEM or use any aftermarket or upgraded types?

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"We're not here for a long time, so it might as well be for a good time" ~ Boomer

2006 Liberty CRD
2006 Rubicon Unlimited (redrubi) - Sold
2000 Cherokee - soon to be gone
2005 KTM 950

I had the same problem. I put a lift on about a month and a half ago and around the first of the year I started having a vibration on decel. I put some PB Blaster on them to get them ready to change and it strighting out. It then started doing it when at speeds. A few days ago I got around to changing them out. Mine were so rusted into the drive shaft we had to toruch them and cool them down to get them out. Only one was bad but went ahead and changed both. IF one is bad I highly recommend to go ahead and change both.

BTW as far as the firestone alignment, can i buy just the lifetime alignment or do i need to buy tires from them?

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Zack A.
2005 Rocky Mountain Ed.
W4ZWA

You do not need to buy any tires. They offer the lifetime alignment as a service by itself. It was advertised in the shop at 169 and on sale for 139. I found on the firestone car care website a coupon for 15 off but it cannot be combined with any other offers.

Where did you get the replacement u joints from? Did it completely fix the problem? I found on tom woods website they have a u joint that has a slight offset (http://www.4xshaft.com/index.html) which is sold under their superflex series or normal ujoints under their gold series. They seem like high quality. Anyone else have recommendations for high quality ujoints?

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"We're not here for a long time, so it might as well be for a good time" ~ Boomer

2006 Liberty CRD
2006 Rubicon Unlimited (redrubi) - Sold
2000 Cherokee - soon to be gone
2005 KTM 950