I just installed some 63" Chevy springs w/dual shackles in the back of my 85 4runner. The ride and additional flex is great, but I have one issue that needs to be addressed. Even though the new front hangers were installed 11" forward of stock (eye to eye), my rear axle was moved back about 2". I think it's pretty cool and don't mind a couple inches of extra wheelbase, but I'm seeing 1" of exposed splines at the rear driveshaft. I'm not sure how much travel the rear driveline has, but I know it's not much.

I can go about fixing this two ways,

1. I could redrill the perches on the axle to move it forward. This is the cheapest way, but I have to run 2" blocks to level the truck. Running the blocks off-center on the axle perches seems a little sketchy to me.

2. I can have my driveshaft lengthened. This would let me keep my extra 2" of wheelbase, but I don't know how much it will cost. I don't know how to take proper measurements to insure I get the right length either.

I'm going to call the few driveline shops in my area to get quotes, but I want feedback on both solutions from this board before I do anything. Thanks.

I don't know much about driveshafts, but I have talked to someone who had their driveshaft lengthened. It costed them about $80

Redrilling perches is not bad, about 1.5" is the max fore-aft motion possible, or you can run a relocation plate:



http://www.4crawler.com/4x4/ForSale/Shims.shtml

For the longer shaft, just get a flange-flange measurement and the shop can figure out the rest. Usually want 1-1.5" of compression on the rear shaft. Cost will vary on lengthening due to the length of the shaft. Usually the ends are cut off and a new tube is installed, so the longer the shaft the more it costs, $80-100 is a good starting point, more if you want to use a heavier wall tubing.

Roger,

So your saying running the 2" blocks with the perches drilled back 1-1/2" shouldn't cause any problems?

I checked around and only one driveline shop would give me a quote over the phone. They would sleeve the driveshaft with larger dia. tube for a cost of $150....blah..

With those axle relocation blocks, would I need to redrill the upper spring plates as well?

Generally yes, since you need a hole for the top of the spring center bolt to come through. It is easier to do these since you can remove them from the vehicle and drill them on a bench or in a drill press, or even take it to a buddy's place or a shop to drill. A bit harder to drill the spring perches, as you need to do it under the truck and the holes are about 5/8" dia, so a 1/2" electric drill and stepped down bit are needed.

You could just redrill the top center hole in the blocks if they are solid like these:





That sounds about right for a longer, thicker tube shaft.

I bought some cheapo steel blocks from Advance that were hollow. I decided not to use them and took them back.

I'm going to add a leaf from my old packs to get the extra lift and will drill the perches.

I'll post some pics when I'm done, thanks for the help.