Sinking Creek 4WD Association

A few weeks ago I picked up a 79 F150 4x4 w/ a 9" rear/D44 front/C6/np205/351m. Engine has has a bunch of recent work but the rest is in need of some work. I'll try to get pictures up tomorrow. I intend to keep it road worthy and drive it to trails.

So far what I have done:
-clean engine bay; paint, sand, and fix leaky valve covers
-replace break booster/master cylinder along with most brake components
-got rid of rusted through bed


To do:
-build tube bed, relocate gas tank, sand and paint frame from the cab back
-debating on lift and tire size
-debating on welding/spooling the rear
-build front and rear bumpers
-paint cab floor with bedliner
-many other small things


Many pictures and likely quite a lot of questions to come.

questions for now:

4" or 6" lift? I have decided on the superflex springs but can't decide on lift, I am very much leaning for 4" for the low center of gravity and being able to do the lift with less worrying about radius arm drop brackets, caster angle, etc. Does everyone think 4" with 35" tires would be best?

If I go with 35" tires and weld or spool the rear would I be breaking a lot of axles or should a Ford 9" handle it pretty well? I am going to leave the front open for drivability and to reduce breakage. What about 36s, they will fit with slight rubbing and fender trimming, but will it be too much for my axles?

Well, you've seen Grubb's truck go. It's got more motor than you with a manual transmission and the 9" has more or less held up to his 36" Q78s. You have the 31 spline shaft "big bearing" 9" in that truck, or should unless someone has changed it out. I think you'll be good to go.

First things first, if you want that C6 to live off-road, you need a BIG transmission cooler and a transmission pan with a drain plug. DO NOT have the transmission flushed. Just put a filter in it and change the fluid in the pan. Run it for a while and with the drain plug you'll be able to just drain the pan and change the fluid about once a year if you do much wheeling. This will keep the automatic happy and alive.

I definitely plan on that, haven't got a pan with a drain plug but I already have a filter kit and pan gasket in the mail, and will be ordering a big cooler, likely with its own fan, soon.

Got some work done on a shackle flip this weekend, whats everyone's opinion on the shackle angle, is it ok, or do I need to move the shackle mounts farther forward?


Truck sitting on its own weight


Truck with rear wheels hanging in the air

When I figured mine I calculated how much the bed/toolbox/fuel etc was going to weigh and set weights on the frame to simulate that amount of static weight. From there I set the shackle angle like I wanted. However, my shackles are designed so they can't flip over-center, which could be a problem with stock ones. I'd say where you have them now is close, maybe move the mounts forward just a touch. Kinda hard to say without knowing how much the bed, etc, is going to weigh.