minimum lift for 2wd to 4wd conversion??

[zakt]

Anybody know what the minimum lift you would need when converting a 2wd to 4wd to clear that 2wd crossmember using a D60 high pinion, 6" or more???

Todd

[willysrul]

Cut it out near the frame and weld some caps on it so you have 2 little nubs on each side. Then box the frame from the motor mounts forward. Put in some DOM tubing for another crossmember further forward and up in between the framerails.
I think if you leave it there you will have some issues when it is at full bump.
Or maybe notch it where you driveshaft would be and weld in some plate to clearance it.
Just a couple suggestions.
How big a tire do you want to run and how much suspension travel would be the concern.

[averagef250]

I think 6" would clear it for normal driving. 4" highboy lift springs will not clear it. I really don't think it's a smart idea to use the 2wd crossmember, it will just cause headaches making everything fit. You're going to have to box the frame for steering anyway, might as well do it right, get all the 2wd stuff and build 4x4 mounts.

A 78=79 HP60 front in a highboy comes very close to the pan. I can't recall exactly how it sits with a V8, but I know you cannot run headers without a 4" lift to clear the front driveline. With a cummins in a highboy and a HP60 with stock highboy front springs there's about a 1/2" of clearance to the oil pan at full spring compression.

If you want to keep your 2wd crossmember the only way I could see it working is if you went with an 86 or newer HP60. The newer ones have a different offset to clear the later 4x4 engine crossmember which is exactly the same as the later 2wd engine crossmember (the late 2wd and 4x4 frames are the same). You have some big steering and spring obstacles to overcome with the later axle though. A minimum 4" lift and crossover steering is probably the easiest way to get things working OK.

[zakt]

Probably will be doing an 8" suspension lift.

[averagef250]

8" more than it sits as a 2wd or 8" highboy/superduty springs? 4" clears 35"+ easily.

[zakt]

8" more as it sits with the 2wd

[averagef250]

4" highboy springs would be atleast 8" over 2wd stance.

[zakt]

highboy has 4" blocks or so in the back I believe then Im wondering if without those is the 2wd height (have to look at my 2wd tonight and see if any blocks )

Todd

[averagef250]

F-250 4x4 and F-350 2wd rear springs are the same. F-250 2wd springs are lighter.

[zakt]

So the front and rear springs are different width??

Todd

[averagef250]

Front springs are all 3". F-250 4x4's and F-350's used the 2.25" rear springs

[zakt]

still debating this.... now thinking 12" over stock 2wd with 37" tires... so what 8" over high boy height. Using a 70's diff offset (Is a 68 D44 the same diff offset as a D60 would be?? Have the D44 for mock up) will the front drive shaft hit that 2wd crossmember (460, C6 with married NP205) Wanting to put a 95 steering box in, will it fit infront of the crossmember....Also have a ford 10.25 in the rear so maybe a 90s front axle is the way to go?? Will the NP205 front drive shaft line up enough with the newer front axle to not cause problems etc....
Todd