Shackle Height

[Jimmy91]

I am trying to lift my back with 2" shackles and Warrior shackles technician told me that on the 1991 gmc jimmy s-15 4x4 that 1.5 is all the heigher you can go or I will throw my driveline out of wack and would have to use shims. Does anyone know the highest i can go without messing with my drive line. I want to go as high as possible without doing any modifications except shocks and shackles. I am not always shure about taking a techs words but does anyone know the exact max height i can go for sure for my jimmy?

Thanks,
D&R

[1993blazerlt]

it is going to vary truck to truck, a longer shackel will rotate your diff up father which will give you bad drive line angels which will lead to eating ujoints. Your best bet will be to get the larger ones and just be prepared to use tapered shims to reduce your pinion angle.

[Jimmy91]

Yes I understand that my brother made his own when he did his larger lift but can I find out somewhere the exact height i can go without messing things up? Maybe someone who knows and deals with them all the time?

Thanks,
Don

[Sparky2263]

The height you can go will be directly related to the material, fastners and bushings used. Getting the rubbers out and using poly or brass will greatly assist in keeping unwanted movement away.

A good rule of thumb is no more than double the center to center length. If you go that far, you'll certainly have to stiffen the bushings up.