Rekindling Old Furnaces, Long Cold

[haolepinoy]

Not my Jeep, but could just as well be, seeing as mine hasn’t moved in almost five years.

Since it’s tucked up under my carport, half-buried in my kids’ toys most days, I don’t think my neighbors notice much. Though there was that one time some high school kid walked down my driveway and presumed to ask me if I’d sell it to him so he could make a rock bouncer out of it. I can’t remember exactly what I said to him, but it was something to the tune of “GET THE HELL OUT OF MY DRIVEWAY!” in the most Eastwood’ish way I could muster.

She may be on blocks, but she sure as hell isn’t so unloved that I’d let some punk use and abuse her to death, wearing some stupid smirk on his face while launching it into a mud hole. I’d sooner let her rust into my driveway… but is that a fate any better? Not really.

I’ll tell you who does notice the Cherokee though. “When are we gonna fix the Jeep, daddy?” So says the five year old who’s only ever rode in it on his way home from the hospital. He was the straw that broke the camel’s back on this project, that sixth passenger in a chassis barely fit for five.

And I think that’s the reason why my Jeep sits on blocks in my carport rather than on blocks in a junkyard. There’s that hope that it’d be something to someday share with my boys. It’s like a familiar place that I’d like to take them to, show them around. Not just a machine. Not just a project. Not even just another Jeep XJ, a dime a dozen in any junkyard the country over.

But a set of experiences waiting to happen, memories, stories…someday.

When, daddy?

That’s the kind of spark that can rekindle an old furnace, long cold.

[humming]

I have that same John deer power wheels

[haolepinoy]

In A Junkyard Far, Far Away | January 10, 2020

Last we saw this project I had just exorcised from the front of the Cherokee all the rusty bits and pieces that make up the front suspension. And the front axle. The underwhelming Dana 30 in its lesser manifestation…the low pinion version.

The thinking behind pulling the whole axle wasn’t simply “why not,” but came from the intention to scrap the original low pinion Dana 30 in its entirety for something else…another equally underwhelming Dana 30, only in its stronger high pinion iteration (but still crap according to the Jeep people with their massive rubber fetishes).

In a scientific nutshell…the high pinion axle is rumored to be 40% stronger than its low pinion twin, and that owing to the direction the gears are cut. On a high pinion, the pinion gear bites into the ring gear, while in the LP it rotates away from it causing weakness under stress. The HP version also provides better driveline angles…blah, blah, blah. It’s totes better cUZ SciEncE!!!

And that’s why I was looking for one to show up under a '97-'99 Cherokee at my local pick-n-pull yard.

Believe it or not it took a really long time for a decent donor to show up. I’d looked at probably no less than ten or twenty XJs over the past four or five years, waiting for a good condition donor to show up. Either a front end collision bent it all to hell, or it’d be a two-wheel drive version, or a four-cylinder-engined XJ with the wrong gear ratio, or some a-hole had already taken it…needless to say, it took a while. Especially with the lack of motivation this project has suffered under. There’s been plenty of other stuff going on between the Montero and the MPV.

But on this January morning…it was like a late Christmas present just for me. Bingo!

And it came out quick and easy, unlike how I remember fighting, sawing, hammering, cursing, and bleeding to get out the original back home.

With this key ingredient finally secured my Jeep Cherokee was officially back underway as a project. And of course, the all-competent MPV would serve as the courier to deliver the parts and the news to those waiting back home.

[haolepinoy]

@humming

I have that same John deer power wheels

People practically give them away once the battery dies…not knowing how cheap and easy they are to replace. Same story on the green Jeep over there. Many miles and smiles on those things…as the bald tires indicate.

This scene is full of dilapidation…that poor blue shell over there the saddest.

[Brian]

Yes. This is good stuff.

Is this the 3.70 setup my other XJ owner buddy mentioned was something of an upgrade?

[haolepinoy]

@Brian

Is this the 3.70 setup my other XJ owner buddy mentioned was something of an upgrade?

All of your XJs in their usual form come with the 3.73 gears. Definitely not an upgrade as far as gears go, especially once you start putting taller tires into the mix. 4.10 ratios are good for 31" tires, 4.56 for 33", etc. It is very rare to find a stock Cherokee in these other ratios, but they did exist in various unicorn configurations (manual gearboxes, 4-cyllinder engines, 2wd, and rare tow packages, mail carriers, or some strange combination of these, etc.). One of the games I’ve always played at the junkyard is a Gearhead version of Pokemon, where I’m always on the lookout for that “ultra rare” animal. Might be going tomorrow to check out an older specimen that just showed up…wish me luck (and pray that I don’t die of heat stroke).

The upgrade in this case is from the configuration of the pumpkin, and more specifically the location of the pinion gear. Low and high are literal descriptions of where the rear pinion gear leaves the case. They came out with the “low pinion” Dana 30 in the 2000 model year since they needed more space for the exhaust routing…since CALI emissions standards were adopted and two massive pre-cats were crammed into the already crammed driver-side of the engine bay. It is a crap cocktail of massive pre-cat-caused heat soak, a flawed head casting, and the low pinion Dana30 that make the '00 and '01 XJ a bit of a black sheep.

The pinion being on the bottom of the case means that where the pinion gear engages the ring gear the two rotate away from each other, causing deflection under stress and grenading. With the high pinion, the p.gear rotates into the ring gear, essentially eliminating deflection, and allowing the weak link to be anything else with the Dana 30 (usually axle shafts or u-joints). The '97 to '99 have the best of all possible configurations of Dana 30 pros and cons: largest spline axle shafts, largest u-joints, best pinion angle. The one I got was a '98. It’s basically the least crappy of the crap.

[haolepinoy]

The real upgrade in all this. New quality parts, ready for another 180k of service. Lots of Dana Spicer or better stuff going into this guy before it finds itself a new life underneath a new Jeep. Good as new is the goal (maybe a little better before it’s all done).

[Brian]

Solid. I think I’ve heard of low- versus high-pinion setups, but only seldom, and this is the first I’ve actually made sense of it. Makes sense that you’d want the pinion biting harder than wanting to deflect. I mean, nuh-DOY.

[haolepinoy]

Project Re-Commencement | January 12, 2020

Getting something from the junkyard always comes with the risk that your new used part is a boat anchor waiting to happen. My first task was to put it up on the bench for a thorough inspection. If the junkyard was to be believed this axle clocked in just north of 93,000 miles of service in it’s first 22 years of life. That’s not very many. Hopefully that’d mean little to no wear where it counts…the gears. Everything else could (and likely would) be replaced.

I popped the cover off to drain the oil and inspect everything, and it looked about as good as I could hope. No glitter in the goop. No chips in teeth. Perfect. Couldn’t really ask for a better donor to start this next stage of the Jeep’s resurrection.

Smell that!? I know you can smell this picture, haha.

[ChazzLayne]

@haolepinoy

Smell that!? I know you can smell this picture, haha.

Yeah, thanks for that. Almost as bad as the 7 quarts of 90w140 I’m overdue to deal with…

Love it when the junkyard scores work out, that axle looks pretty darn good.

[haolepinoy]

Stripping Down the Donor Axle

With the irreplacable bits inspected and determined to be fine and dandy, I got down to stripping the rest of the axle. Off came the unit bearings, out came the axle shafts, and off popped the knuckles. Of course it wasn’t that easy, but it wasn’t that hard either. Lots of banging, whacking, prying, burning and the rusty parts finally surrendered.

As expected, the unit bearings are completely knackered. Mr. Timken will sort that out for me with some new pieces. I might try and save the hardware, and employ some of the science I’ve been learning from the riding lawnmower project. We’ll see.

The u-joints were essentially toast. Mr. Spicer himself hadn’t intended them to hold up under 22 years of service, so I wasn’t expecting anything more. Plenty of wiggle. These will be getting replaced, and modified with a bit of an upgrade.

The shafts themselves, aside from a bit of surface rust were in decent nick. I’m not sure what to think about the threads on the end of the stub shaft. I’ll try reworking or retapping those threads. My guess is that that is the result of applying 175 pounds of feet to the threads. They’re not stripped or cross-threaded…just flattened. I’m hoping a new nut will have enough to bite down on…

[haolepinoy]

Stripping the Donor Axle, continued

I rented a ball joint removal tool from the local store…they’re a shit show. I never leave one of their stores without thoroughly checking the tool that I’m borrowing. They’re almost always broken, missing pieces (the one you need usually), or some other version of useless. I hate the concept of renting things. It exposes the worst in people. People destroy what they rent because it isn’t theirs and they could care less about treating somebody else’s stuff with the same kind of respect they’d expect their own stuff to be treated with. I could go on and on and on here…but who cares. But in this case, it took the combination of three, yes THREE ball joint removal kits to come up with one that had all the pieces in it I needed. Oh, and a bungee cord to hold the case shut so I could leave the store. Once home with the “proper” tool, thirty or so minutes was all it took to remove the ball joints. They’ll be replaced with some OEMs.

The upper control arm bushings came out with some good old fashioned brute force, but in the case of the passenger side tower I needed to use some shade tree ingenuity to keep from bending it all to pieces. A “spacer” was inserted and held in place with a random assortment of clamps and prayers in the hopes to prevent me from ruining things. After much frustration and dumbass’ery, I prevailed.

The sway bar end links were basically just rust and dry rot at this point, nothing more holding them together. Into the bin they went, but the pins that attached them to the axle needed to go. They’ll be replaced by some upgraded quick disconnects from Mr. Currie in the future. More pounding, but this time aided by a torch.

And with the exception of the inner axle shaft seals that I’ll remove later, that is the donor axle all stripped down and ready for some refurbishing. Among the peasants there was much rejoicing.

[ChazzLayne]

I feel ya on the rental tools, shenanigans only amplified by the cursed nature of all ball joint tools. I gave up and bought not one, but three sets of ball joint tools before finally arriving at the correct combination of bits…which still required making a custom tool out of one of them with a grinder. Rental woes aside I swear there’s just something unholy about the tool itself.

Glad to see I’m not the only one that hits them with the rattlegun.

[haolepinoy]

@ChazzLayne

Glad to see I’m not the only one that hits them with the rattlegun.

“Is there any other way!?” - Sir Isaac Newton

[haolepinoy]

Stripping the Original Axle, extra credit

For upwards of four years, underneath my Cherokee has sat this unloved relic. I haven’t held onto it for any sentimental attachment or hoarder’s mentality. The plan has always been to strip it down as well for the sake of several useful spares. Despite the difference in pinion location, most other things are interchangeable between the two Dana 30 variants.

First step is draining that sweet, golden nectar. You can tell it’s sweet by looking at all the pretty glitter in the drain pan. There was no noticeable damage to any gears inside, but after 180k miles I’d have been shocked to see nothing glimmering in the bottom of the pan. I’m actually shocked I saw none in what I drained out of the donor axle. I guess it’s all about the miles. The donor has only done about half of what the one it’s replacing has.

The spares I’m after are those parts that are prone to being damaged: the axle shafts, the knuckles, the diff cover, and the yoke. I’m also gonna snag the brake dust covers, since the donor axle’s were manufactured in Switzerland, patterned after their cheese. The ones on this, despite having some rust themselves, will clean up good enough after a little reshaping and a coat of paint.

The axle shafts had all of the same issues that I found in the donor assembly, only moreso. More rust. More thread damage. More u-joint play. But like the dust shields, they’ll clean up fine and serve well as spares if/when the eventual breakage occurs in the future.

[haolepinoy]

U-joints, Still Twirling Twenty Years Later

I wonder how many turns these things have taken? In their defense, they’ve held on tight for every revolution along the way. The rust probably helps the hold. Thus the twenty ton press.

I tore down all four axle shafts at this time, two from the donor and two from the original. Of the four, one was still in decent shape.

But the other three proved the prudence of replacing all this used stuff. It was used up years ago. Bravo Senor Spicer. You done good. We look forward to working with you again in the near future.

[ChazzLayne]

Wow, any idea what kind of mileage they’ve seen?

I once ran the stock u-joints in my '97 TJ down to an egg shape, about 70% material remaining. My first real introduction to mod-related problems and it also happened to be proof you can cause death wobble without any steering/alignment issues…it was all from the front driveshaft.

[haolepinoy]

On one axle the u-joints were 93k miles old, on the other 180k. I’d assume that the nasty ones in the pictures above were from the later.

[Brian]

What caused those joints to get so corroded? (I’m new to anything beyond CVs.)

Loving the pictures!

[Rob.E.Thirty]

Grease wears out, maybe water gets in and dirt too. We used to get zirc fittings on u joints that would help to reduce this kind of failure provided you greased them but I imagine in an attempt to save some money they got rid of that feature. You can still get them in the aftermarket last time I looked. Some of the equipment I service has around 40/50 zirc fittings to keep all the various moving parts in good working order.