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GMT800 2wd to 4wd Stock IFS or SAS?

4Eyedturd

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Waco, TX
My daily is an 02 2500 2wd, and I have a wrecked 03 2500 HD 4wd chassis. I was contemplating cutting the front clip off the 03 and using it for brackets and measurements to install the stock 03 diff in my 02 then find a manual transfer case but how much more work would a SAS be? The pro to the IFS is I can use off the shelf parts for everything and I already have the front diff and I could probably do most of it in a weekend and keep driving it. What would Irate do?
 
Your current plan is to fabricate the 4WD IFS onto a 2WD truck and you have reservations about the difficulty of a SAS?
Not much fabrication with the 2500s as long as its got tbars
Pretty much bolt on to convert to 4wd
 
IFS- 3tabs welded in, 2 recessed holes for bushings welded in

SAS- briefly looked over a SuperDuty swap

Stock or close to it height

IFS stuff seems like I’d have the least down time. Tim ZR2 had a good build on PBB
 
Negative that would be to easy DD is crew cab short bed and wrecked truck is extended cab short bed.
 
I feel like a SAS will have you sitting around 6”+ taller than a stock IFS truck, depending on the setup and springs. Had a 2010 that I briefly thought about swapping. The ORD setup was the cheapest option, but it would sit fairly high. The lower
 
Just SAS the 02. By the time you swap everything over, it would have amounted the same costs and headache. There are some things you need to do to make the 02 4wd capable.
SAS is always the answer.
 
I feel like a SAS will have you sitting around 6”+ taller than a stock IFS truck, depending on the setup and springs. Had a 2010 that I briefly thought about swapping. The ORD setup was the cheapest option, but it would sit fairly high. The lower
Not if done right.

WFO has the 05+ D60 in a Chevy down. The owner, Trevor, has a ~2010 and I walked past it a few times without even noticing. The only thing that caught my eye was the manual hubs. It was about "leveling kit" height.
 
Wfo 3” kit

easiest way to go. It’s spendy, but they’ve already done all the engineering and have done it well enough to sell it to the general public. It’s all weld on, and not much more work than hot glue gunning the ifs in there.

Kind of forgot about that due to the price. With the initial kit being $2800, you’re looking at $5k+ by the time you buy coilovers, the axle, misc. parts. Probably not a bad way to go if you want to keep the truck as a capable DD though.
 
If it was a vehicle you’re building for the long term, it is probably worth the price. I never got past a few days of researching for the 2500 I had because I never planned to keep it long term.

The IFS components I stuck on my 2010 were around a $1K. That was new UCAs, shocks, TREs, etc. Last I looked, some of the long travel IFS kits for a 2500 were about the same cost as what you priced above for a SAS.
 
What’s a 05+ SD axle going for nowadays?

Depends on the area. I'm not far from you and I generally pick them up (read: hoard) for $3-600 complete. Then a rebuild (bj's, shaft joints, seals, etc.) I can get into one cheap, or higher than eagle pussy.
 
Im in the middle of SASing a 2005 2500. a little different application since its a trail rig but I have blown my budget for the project several times. As we all know the little parts can add up quite a bit and things get spendy quick. however I think that if I was going to build a daily driver I would jump on the WFO kit if your keeping the truck long term.
 
Like I said, it’s spendy.

I mathed it out at around $8k including buying and building the axle, new brakes, adapters/spacers for the rear, and a set of sd take off wheels. To me that’s worthwhile for the problem solving they have already gone through for me. The hours I’d have into making a set up work as good as theirs from scratch in my garage is stupid high. The math works out in their favor even considering my time is nearly worthless

Leaves are simpler and cheaper, but you have to go higher with them. 3” is about right to me. Not too tall that it’s a pain to daily, but it will still clear 35s easy.

Another option is to grab the pieces you want from wfo, like the arms, frame plates, steering, and scab some coil buckets and shock towers onto the frame.* It would definitely keep cost down not jumping into coil overs

*I haven’t done the slightest bit of measuring to determine how feasible this idea is.

WFO has that as an option. They're a little more expensive than factory Ford coil buckets, but they are spaced out properly to line up with the coil spring mounts on the axle.
 
Sort of like this?

I used Barnes coil towers and ford shock mounts, with the WFO radius arm kit. 2014 F350 front axle, with matching Sterling rear, with e locker.

it's on a C30 crew cab chassis. Ignore the IH cab. :flipoff2:
 

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Fuck I can’t find a manual transfer case, are they rare or some shit? Then I got to figure out the speed sensor stuff and changing the ass end of the 4l80 over to 4wd.
 
Found a NP261 LD today for $200 in unknown condition. Grab it or keep looking for a 263HD?
 
I think I’ve got it all pieced together for an IFS swap. The electrical is the last bit, I figure I can put a switch somewhere on the dash for the front diff but do I need to hook up the other speed sensor on the transfer case?
 
I think a lot of this will be easier than you expect...

Here's what I gathered building a 2005 Chevy van with 4wd ifs, 6.0 4l80e np241

The front ifs swap should be pretty easy, mostly welding in a few brackets from the donor frame

The 2wd 4l80e has like a 95% chance of being a full length splined shaft (32spl)

You pull the tail housing, stick foam ear plugs in the holes, cut it down, maybe have to grind on the fatter part of the shaft some to clear the t case input

There's a little, 3/8" or so freeze plug with an orfice in there, that's gonna flood your t case, you need to swap that with the $10 a.c. Delco plug

I didn't do much 4lo, it did fine manually shifting 1st and 2nd, kicking on the ABS light, and quickly clearing when adjusted back into high, and restarted

Being a truck, maybe your pcm has an unused 4lo file, or maybe it's a simple flash if needed

My tow rig is a 2005 2500hd diesel with 35s and cranked torsion bars, I've considered a sd d60 swap, but don't really want the extra height, and really really don't want the cost and complexity of coil overs

I've wheeled mine out of necessity, for example dragging a car trailer down a jeep trail to recover a broke down truck, I'm satisfied with the components, just need upgraded tow rod ends, and keep the old ones, and the tools, in the toolbox...
 
I forgot to mention that the front diff actuator was pretty easy too

I forget if it was a momentary toggle for engage and disengage, or if it was power to engage and it disengaged with no power, I forget, but it was self explanatory

The actuator has a switch inside that closes a circuit when it's fully engaged, I used that to trip a small led light from Amazon.
 
I have 2 ecms from 6.0/4l80/ 4wd trucks (99 & 03)I thought about swapping in after I wire in the other VSS but they were from electric transfer case trucks. Not sure if that matters or see if I can flash a 4wd tune to my 2wd ecm.
I’ve got a front 4wd subframe I’m using as a jig to make the mounts in my 2wd frame and it has the front diff.
Found a 4wd rear driveshaft
Found a floor shifter with linkage and bezel
Found a 261 and 261 LD transfer case and a front driveshaft. Gonna clean them up and check em and see which is in better shape.
Gotta find that rear plug for a 4l80e still
The parts truck was a 03 HD so I may swap in the beefier 14bolt, gear ratios are all 4.10’s and hopefully the newer on has a decent G80
 
I'll look for that plugs acd pn, it's not super elusive

I wouldn't worry about the ecm, until it's all done, you'll have 4hi, with no issues, then maybe inconveniences with 4lo, don't let these things slow you down...

That said, my tinkering was all 05or 06, and I didn't need any vss stuff, or t case sensor, my van diff had 2 wheel speed sensors for stabilitrac, which prevented me from upgrading my rear diff

I would verify your front and rear gearing on an unknown purchase, for sure:laughing:



Edit

This is the one I bought for mine

ACDelco 9427692​


Also, if you haven't already replaced your oil pump pickup o ring, do it before it's 4wd and adds 4 hours to the job:laughing:
 
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IFS 4wd swap took about 3 weeks with a week of being sick. Went from auto/2wd to 5speed/4wd without to much hang up. I used a KB diesel metal clutch pedal to get away from the cheesy plastic clutch pedal which wasn’t to bad to install. Then found out the 5speed is a little shorter than the 4l80 so I had to shorten the front driveshaft a **** hair and the rear shaft has a little extra stick out.

Truck has 4.10’s and 33’s so first is steep as fuck but the truck doesn’t have quite the balls to start off in 2nd without clutch slippage. Shorter tires are easier to install but I’d rather find 4.56’s to make up for the 33’s.
 
Picture a stock looking 5speed, 4wd 99-02 truck because I used pretty much all stock parts besides booger welds holding the front diff brackets on. Truck is doing surprisingly well on fuel economy around town until I took a trip to Gatesville, 70-75mph and it seemed like I could watch the fuel gauge drop. 75mile round trip seemed to use half a tank of fuel. Not sure why yet
 
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