- - Need SYE
04-05-2006 09:32 AM
I just put an RE 3 1/2" lift on my tj. Somebody told me that only 20% of the time do you need to do a SYE if you drop the transfer case 1". I must be the 20% cuz I can't adjust out the vibs and they're not acceptable at 50 mph. There are several decent kits that I see. . . what's the best? What's the best driveshaft to get? I looked at the Tom Woods stuff, but can't really tell what I should get. . . Any help will sure be appreciated.
04-05-2006 10:15 AM
Tom Woods is a great driveshaft company, and you will get great service. As far as the SYE kits go, most are similar, but you probably want to stay with the kits that include a new rear output, not one that you have to cut yourself. Other than that, I don't really know much about them, sorry.
04-05-2006 10:51 AM
Another trick that is cheaper, is to get the Nth Degree adjustable upper control arms, and tilt your axle back to improve your drive shaft angle. It doesn't take much, and will not hurt anything. If your kit did not come with longer lower control arms, that could be why your having a problem.
04-05-2006 11:33 AM
I used the adj uppers on mine to correct the angles, but I had to tilt the axle down to get the angles right.
Your tcase output should be parallel to the pinion output shaft and as long as you don't get the ds angle too steep doing this this will work.
Since you have to have the adjustable uppers for the SYE kit anyway you have not lost anything by doing this first to see if it works.
04-05-2006 12:04 PM
I have the adjustable lower control arms. I've read two things: one that I need to make the u joint angles as straight as possible. The other is that the tc u joint and the ds u joint need to be tilted to complement each other, thereby reducting vibs. I started out with the lower control arms one turn longer than the stock length and I've tried both. I'm having trouble visualizing why I need adjustable uppers - what do they give me that the adjustable lowers don't?
04-05-2006 12:14 PM
adjustable control arms
If you have the lower adjustable control arms, that will keep your axle in the right position in the wheel well. It should also keep your drive shaft angle in the correct position. If you have a 5 degree angle coming out of the rear of the t-case, you should also have a 5 degree angle at the axle yoke. From what I have been told, you want the same angle at each end of the drive shaft. The upppers should not need to be replaced if you can achieve this with the lowers. The adjustable uppers allow you to roll the axle either direction quicker than the lowers do. Just remember that making the lowers longer, will make your axle want to do a nose dive at the driveshaft connection.
04-05-2006 12:40 PM
A 1" motor mount liftwill probably do the trick, but do the 1" body lift as well.
04-05-2006 05:16 PM
From what I understand you do want the ujoint angles as low as possible, but that will have to be sacrificed to get the output shaft and pinion the same. Apparently the output/pinion angles are what causes vibration and as long as the DS angle does not get excessive you should be able to clear the vibrations.
If you already have the lowers you should be able to set the angles with them but if not purchasing the adj uppers is what would be required IF you had to go to a SYE setup.
Go grab an angle finder from Home Depot for less than $10 and take angle measurements on the output shaft and axle housing and adjust the control arms until the angles match.
04-06-2006 11:39 AM
Just ordered a RE SYE kit and shaft. . . might as well do it right.