taskswap

Well I haven't got a definite answer yet. But I'm LEANING toward welding the spiders. If I do turn this into a plow vehicle it will live out its days almost completely on dirt roads and typically only be driven to plow - with snow on the road. So the usual drawbacks like being terrible on paved roads wouldn't apply. I'm not 100% sure this is a good idea, yet. Small ATVs with plows come up on Craigslist all the time pretty cheaply and for light duty like this would be fine. My daughter loves Rocky and is insisting on keeping it set up the way it already is. I'll report back once I decide either way

That seems to be my experience so far. Lots of "this is an easy install!" threads and videos from guys that seem to tear down and build diffs and axles as a weekend hobby (not me) and not so much "this is your truck, we know your truck, buy this and it will work..."...

Thanks, guys. So this Eaton... Their application guide is a little confusing. It's been a year since I verified these notes but last summer I spent some time figuring out exactly what I have and my notes say "Axle 42 = Dana - Capacity 6250 - Ratio 3.73 Dana (Spicer) 30 Spline 10 bolt cover 9.75" ring gear Looks Like A Standard Dana 60, But Has A Different Offset For The Carrier". Any of that sound any alarm bells for you? From Eaton's application guide if I choose Rear, 30 Spline, "3.73 and Down" plus "3.73 and up" (because I have no idea what the diff is I get two results: 913A315: DETROIT TRUETRAC® DIFFERENTIAL; GM 8.875 IN.; 30 SPLINE; 3.73 AND UP 913A589: DETROIT TRUETRAC® DIFFERENTIAL; DANA 44 FRONT; 30 SPLINE; 3.73 AND DOWN Neither screams "this is the one" and their detail pages are unhelpful too. One has notes like "For use with non-thick ring gears only." and the other says "All Eaton differentials made for General Motors 8.5" and 8.6" axles require special bearings. For axles with small bearing bores (race O.D. or 2.89"), usually found on vehicles prior to 1999, bearing LM102949 and race LM102911 are required. For axles with large bearing bores (race O.D. of 3.06"), usually found on vehicles from 1999 to present, bearing LM603049 and race LM603012 are required.". And they list different ring gear sizes of 8.875" and 8.5" neither of which match mine. Do you happen to have any idea what part numbers y'all might have installed?

Guys can I revive an old and horse-beaten topic? Rear lockers. But maybe with a twist? I've had a health setback (stroke) and I'm reprioritizing some projects. Everyone in the family loves Rocky and I have no plan to sell it, but figuring out what to do with it has been a challenge. I'm the only person who can drive stick (very well) and I don't really want to think about an automatic conversion. It's also obviously never going to be a show truck. We have a homestead here in CO where it can while away its years (just like me LOL) but the most useful thing I'd do with it aside from runs into town is plowing. Not a lot of plowing, mind, but we have a dirt access road with two spots that collect snowdrifts, each about 30' long. It's enough to be a barrier for most vehicles in winter, but as you can imagine this is no great workload for even an entry level plow setup. It's a straight "push it to the side to make a path" type of work effort. The trouble is, Rocky is 2WD. All the other specs are great - '81 F-250, 6.6L V8 351M that starts instantly even in the dead of winter, etc. I've got some chunky hybrid-mud tires on there, too and I can keep chains on it full time because it's all a dirt road from the property out to the main highway. But it's still very tempting to try to do something about the stock rear axle (a Dana 61 at 3.73). I know lockers come up in discussion a lot but all the past threads I've seen have focused on daily drivers, people wanting "hunt trucks with highway manners" and so on. But what would you do if you had the opposite situation? Suppose you wanted the fastest, simplest option to give something like Rocky more grip in snow and mud, and on-road behavior was almost never important? I'm not super driven by cost here but mostly because I figure the most costly options are probably not the first choice anyway... I do have some skill at welding but only moderate so I'm not sure I'm up to welding the spider gears properly. Everything I see seems to mostly focus on Dana 60's. I know the 61 is essentially similar but with a few clearance/spacing differences but I don't exactly have a machine shop in my garage. And given my health issues I just can't see trying to pull old axles from junkyards at this point. Is there a purchasable, bolt-in option of some kind that a shade-tree mechanic could pull off that would at least add some snow/mud grip for this kind of occasional use?

I don't know if OP is still looking for a lug solution but just to put a pin in that, I did replace my (stock/left-side) lugs on both my discs (front) and drums (rear). I used these: Dorman 610-228 Rear 9/16-18 Serrated Wheel Stud - .625 in. Knurl, 2-25/32 in. Length Compatible with Select Ford Models, 10 Pack https://www.amazon.com/gp/product/B0011N1K7C The listing is misleading, this is for a box of 10 (they aren't $22ea!). But they installed quite easily, I thought. I didn't need a press for removal or installation. I just set the disc and drum over a cinder block and used a 2lb sledge to drive them out and the new ones in. To seat them fully I used a pair of washers with a small dab of grease between them as a temporary bearing and an open-end lug nut plus a deep socket impact to draw them fully in. It was really fast an easy.

If anybody wants a guinea pig to try something from a vendor/eBay source/etc for fit, I'm about to rebuild my '81's steering. Main goal is a steering box rebuild but I figured I'd replace the shaft while I had it apart. I don't mind buying something that doesn't work out / can't be confirmed if it helps the cause to confirm that.

You're right. My option is only for a 2x4. Have you considered moving the bumper forward? This is a relatively easy thing to do, a little ugly but hey it was a chunky beast to begin with. You don't need to move it forward the full depth of a winch. Just 6" or so. That's about enough that if you fabbed some bull bars up it would sort of look like it was meant to be that way...

That might have been me - I was working on doing this in Rocky. I never completed the task but do believe it's possible. The Rocky build thread is pretty long but if you page through it there are a few pages of folks helping me brainstorm this. I was going to use this winch plate: https://www.amazon.com/gp/product/B08K7J1SSH. I see it's no longer available, but it's a common item other vendors sell. You just need the same rough dimensions. What I found was that this plate will JUST fit between the front frame rails, at least for my '81 F-250 (2WD). The fit isn't perfect, you have to notch the two rear corners, but it's very close. It rests on the frame rails just enough that if you drill your holes right, you could get one bolt down through them on each side. Then I was going to make side brackets out of some 4x6" angle to connect to the sides of the frame rails, and finally I was going to use two pieces of angle iron to make 45-degree reinforcements from the rear of the winch plate to about a foot or so further back on the rails. This would help make a winching load more of a "pull" to avoid twisting the frame rails. If you want, I can sketch all this out and send some pics of what I was up to. But no guarantees on fit, you'll need to mess with it a bit. You need a very low profile winch. I went with the Zeak 12,000lb: https://www.amazon.com/gp/product/B07MXBXV44. It's total overkill and you may want to go smaller. You will not have room to mount the control box on top, obviously, so you need to plan that out. There's plenty of room in a Bullnose to stash it somewhere behind one of the headlights, but the cables that come with most control boxes aren't long enough so you have to extend them. And with heavy duty cable, too, so plan for that. You also won't have access to the free-spool lever. I had planned to work out some type of extension, probably just a simple steel rod with a pair of u-joints top and bottom to allow for a bit of misaligment when you route it behind the grill. I was going to try to have this come out just under the hood, in front of the radiator, so you'd pop the hood and it would be there. I didn't see a good way to have the handle fit, so I was going to use a long socket extension as my rod, with the "socket" portion at the top, and just use a socket wrench (or make something simple, welded) as a removable handle. They make fairlead hinge plates to hold a front license plate, a requirement here in CO, two plates. I was going to put my fairlead right on the front bumper, a low profile fixed one, not a roller style. (One came with the winch.) And then the plate on top of that obviously. You have to cut the bumper to do this. I'm 95% sure all of this is doable. But it takes some doing. The biggest angst is drilling the frame rails. You're going to weaken it where you do that, which mostly isn't that critical because the only spot the winch could possibly sit is RIGHT at the front, and this happens to be forward of anything important. Bear in mind these frame rails were never designed for winching loads. I'm not a structural engineer, but you can tell just looking at them that they're pretty thin. The area we're talking about normally has only one job - holding the front bumper. Aside from the bumper's weight, the only load it should normally ever see is in a collision, so it's designed to resist being pushed, not pulled, and even in the 80's they were figuring out crumple zones for safety so I don't think it's meant to be massively strong. If you have welding skills, you may want to consider welding reinforcement plates into the area. I wasn't planning to use this much. I just happened to get a great deal on a 2WD when I really wanted a 4WD. In my opinion, a 2WD can go a lot of places you'd normally want a 4WD for, if you have a winch and some determination. I wouldn't be off-roading with it, it was just going to be a safety feature. We have a homestead with a long, hilly dirt road. In the winter, mud and snow can make it really difficult to get up and down, there's no cell service, and even if there was, AAA would be over an hour away. My thought was if I got stuck I could self recover using the winch. As long as you aren't too bogged down, sometimes even a few hundred pounds of a straight pull off a tree is enough to get you through something in a few minutes that would have been a half hour messing with traction boards and shovel work.

Hey folks, been lurking for awhile but I'm still here. I just brought Rocky home from storage last night to get some more work done on it over the winter (I've been homesteading all summer, different project). And it reminded me how rough it runs at low RPMs, especially while cold. Rocky has an aftermarket Holley Street Warrior carb that the P/O installed and I've really struggled to tune it. I've got it more or less to the point where during the summer, it runs and sounds great, but I keep blowing fuses on the electric choke line for reasons I haven't figured out, and during winter (now) it's really hard to start and get idling properly. Once it's warmed up, that goes away, but it always stumbles off the line like at a red light if I don't get it up to like 2000rpm before letting the clutch out. It feels like the low-RPM fuel starvation issue lots of folks have to tune around with poorly-installed Holley's. I'm sure with more time and effort I could get this thing dialled in, and I'm sure I could also pay somebody to really nail it. But I don't really need this truck to be a "beast," I'd rather more of a daily driver that my wife could use as a backup at this point. She has a lot of experience driving manuals but Rocky is just REALLY "testy" right now. So now I'm starting to think about reverting to a stock carb. Has anybody here done that and for similar reasons? Is that maybe the best path, or should I keep tuning this since it's already there? Appreciate any thoughts, no stupid ideas. :)

Well that sure is like looking in a mirror. Aside from the cargo tie-downs that's basically my exact truck. Do you know what month it was manufactured? Wondering if you still have slide locks like I do. I've got nothing helpful to add on the bolts, though. I've had luck with drilling bolts out using carbide drill bits, it takes some time (cutting fluid helps) but if you center-punch your bolt heads accurately and step up from small (1/8"0) to large sizes it only really takes 20 minutes per head or so. That works for replacing riveted parts too like ball joints on control arms on some cars. Hopefully one of the gurus here has a better tip...

Well that sure looks familiar :)

Side anecdote, I tried that "Guaranteed To Pass" (GTP) product and it did work for me. It's not a permanent solution but if you're just trying to squeeze out "one more year" it might push you just under the limits long enough to pass...

Is that one of those hard-to-find parts I might want for my '81? I'm not clear whether it's a common replacement item or not. My steering is very squirrely and I was planning on rebuilding it this spring...

I want to put a set of those on my wife's Chrysler Pacifica :)

Can't wait for the trip report on this one!