Converting stock 2wd to stock 4wd

[faraiwe]

I call this shot "Hopeful Synergy".

It contains everything harvested (from a single '99 XJ donor vehicle); trans with transfer case, assorted screws and fastener plus wires, goofy auxiliary shifter linkage, trans cross-member, front axle with diff plus assorted linkages, front driving shaft, new trans fluid filter and gasket, bottles of varied fluids (diff oil, brake cleaner, lithium grease, sealers, WD40, ATF and all-important Gojo). I plan to re-use a lot of screws and other small minutia from my own currently installed parts.

I am also getting an after-market rear diff cover, because that shameless rubber plug annoys the living beejeezus outta me. :nosmile:

But for that suitable rear shaft, here I go. I am hitting the yards again. eBay seems to have a few options, but overpriced, and no one seems to be able to verify if the drive shaft's spline is compatible with the rear differential. :tear:

INCIDENTALLY... before I even advance. I THINK I have a Dana35. There's some spray-on material over the markings (it resisted power spraying at 1400psi), making reading them a feat of imagination. An XJ differential identification doc seems to confirm this, but it's all I got to go on. Two marks SEEM to say "TB4 HS3760" (??) and "<Chrysler Star>12767 52809336" (???), but can't find anything else. The diff has the ten-bolt cover and left side bulge, with the mentioned rubber plug. :helpme:?

 

[kastein]

52809336 is the important number here, that's the part number.

http://www.allthingsjeep.com/atj11127.html

Does your diff cover have flat upper and lower edges? A 35 cover is oval, rounded all the way around, while an 8.25" cover is straight along the top and bottom edges and almost round at the ends. An 8.25" also has two triangular points that hang out at the bottom of the casting right by the bottom edge of the cover, they make the lower edge of the casting flat as well. The edge of the cover has a half-round stiffening flange pressed into it most of the way around while a dana 35 cover has a straight cut edge. I've never found a rubber plug to be a very reliable indicator (my 8.25s have all had a rubber plug as well, some 35s did while some didn't.)

I can't find any info on that part number offhand with google, don't have my parts catalogs handy either.

 

[faraiwe]

Cover is oval, definitely. It looks like the Dana35 on the doc ( http://www.xjjeeps.com/pdf/differential_axle_identification.pdf ), but the part number ( 52809336 ) doesn't seem to pop up on any search. I just wanted to make sure, from folks who have seen and handled BOTH.

Curious: If the rubber plug may or may not be present, wonder if there is a way to tap and drill a plug into that cover, without messing it up, or just picking up an after-market one is less hassle (but more cost effective??). That plug makes me feel as secure as if duct tape were holding the drain; not good for my paranoid self. :eyes:

Any insight/guidance on getting a cover? I'm not trying to go for uber-duper rock-crawler here, so I am not thinking $200 for a cover with titanium bulkheads and minigun turrets, along with a force field, but don't want to get some "meh" excuse for a cover.

 

[faraiwe]

Update. Post holidays craziness. Hands on, right? Right.

Now, this is odd. I have purchased the differential cover, assuming (under the advice and considerations above) a Dana35 differential. Got a D35 cover, got all ready and the such for a change of gear fluid (*), before I actually do the conversion.

As it turns out, a D35 cover has the same shape, same bolt count but not the same size of my differential. This is what puzzles me, here. The diff in place now has the oval shape and bolt count of a D35, but seems slightly bigger. The shameless rubber plug (see interesting story below) didn't have any useful information on it. I am stumped over this. Which does not mean I didn't get to do the fluid, nosirree. I'm too much of a hard-headed, blowhard bastard. Let's just go ahead and appreciate the following images:

Now, gentlemen, put the lotion and kleenex away. Anyone has a clue what differential could this be? I REALLY would like to change that cover. As it is now, I had to improvise a plug (long story, but it involved a dremel, the original rubber plug and an universal oil pan adjustable plug).

So, it doesn't SEEM to be a Chrysler 8.25... the id images look flat on bottom and top, not the case here. It does not seem a Chrysler 9.25, the cover is oval, and edges are rounded, not octagonal. Shapes are wrong for the Dana 30, 44 and 60, altogether. It's entirely different from the Ford ones, and the AMC model 20 also doesn't seem to fit the bill.

What the hell do I have under there?? The vehicle is original, 2WD, '99; "Sport", not the "Classic" trim. I can fetch the VIN if that would help. :banghead:


I want to get facts straight before I go to the diff cover seller with a crowbar.


(*) decided to do all fluids involved - trans ATF an filter, diff, etc - beforehand. How wise is this? Time will tell. How wise I am? You can already tell. :confused1

 

[lawsoncl]

If you got a stock D35 cover with a metal plug, then it's from an early D35 non-clip axle (Renix era I think). Double check the height of the fill plug, btw. The non c-clip version didn't use the gear oil to lube the wheel bearings whereas the c-clip version did. So the older model didn't need the fluid level as high in the housing. As I recall the rubber plug was higher, closer to the centerline of the axle.

 

[kastein]

I could swear that is an 8.25 you have there. Looks like an 8.25 cover, it has straight top and bottom edges and appears to have a half round edge rib pressed in. I also see the side adjuster retainers on the carrier bearing caps. Mind taking a picture showing the outline of the bottom edge of the housing under the ring gear, I.e. move your viewpoint 3 inches down from where it was for that pic? That will tell for sure.

 

[faraiwe]

*Sigh*

So, yeah. It's a Chrysler 8.25 ... with a round(ER) case.

Actually had to get in touch with some numbers in the FSM, which were no longer valid, but eventually tracked down another... long story short, managed to get a hold of someone, and gave them the weird numbers and picture. It seems the Chrysler 8.25 is a bit different after 97, when they altered the casing a bit, so it looks a LOT rounder, also changing the spline count to 29, from 27. This is still to be confirmed, but I have no reason to doubt it.

The mentioned gentleman also mentioned the 8.25 is a substantially tougher differential, apparently used in the high end Dakota and RAM. Go figure. Any input from experience on this, anyone? He could not tell me, from the numbers, if it was a limited slip, so I'll have to do the free-wheel test on a lift, eventually. One can hope? Also, that would mean I'd have to add the lim-slip fluid to the oil (using 80w90 GL5).

I'm not sure how - or IF - that affects my seemingly perennial quest for a drive shaft... Double sigh.

 

[kastein]

That is a non limited slip (ie regular) diff there. You can tell from the shape of the carrier - a limited slip one will have a cylindrical body with a flat end on the housing by the bearing further away from the ring gear while a regular one has a more football shaped carrier with a conical end.

He's not quite right - iirc the dakota has the 9.25 or 9.75 inch diff. It has an almost octagonal cover, iirc.

 

[foxwar71]

He's not quite right - iirc the dakota has the 9.25 or 9.75 inch diff. It has an almost octagonal cover, iirc.

Dakota's got a 8.25 with the small 6 lug pattern, Ram 1500's got the 9.25

 

[faraiwe]

Ah, so no special fluid. Checkmark, less crap to acquire and worry about.

Re: the Dakota and/or RAM, I've seen them with the octagonal for the 9.75 as well, but I just spotted some places online selling stuff for the Dakota and the RAM, with stuff for the 8.25. So, FWIW. I am not into trucks, so I never paid attention, or wanted to know for sure.

Back to the XJ.

You mentioned a *while* ago, it probably had the 29spline, and that enforces what the guy said, so let's go with that. Since it's not a D35, would that affect the shaft, other than spline count? Do they both have the 3.55 ration, dealing with same torque from the shaft? What should I keep in mind regarding the shaft, taking this new find in consideration?

Also, I'm getting fed up with waiting for available voluntary help. Every time I arrange for 2 or 3 buddies to help me, something happens. I can't even fault them, because I lived the same mini-deployment-to-home-to-training-to-deployment cycle. Their time is precious, whereas my time - thanks to govt hiring freeze on intel resources - is suitably devoid of much use aside school books (don't get me started).

So, I am THIS close to accepting taking it to a shop and merely accompany the process as close as I can. Might cost me a pretty penny (from 1000 to 1500), but waiting forever will both cost and achieve zero. Can;'t do it by myself, since I lack the facilities, and well over $2000 in tools which a shop would possess. With the friends, we would have used the base's auto craft shop, rent a lift and jacks for the trans, and spend two afternoons tinkering and cursing. I'm bummed.

The idea would have been to learn and increase and exercise our vocabularies in the four-letter-word range, while having fun. Well, I did SOME reading and research on the minutia, all I am missing is the damned hands on. Assembling a group of volunteers seems precarious, and I have pretty much no buddies around, who are not in the camouflaged life style. I can't simply waste those sweated-for parts, and my babe deserves to be a full fledged Jeep. Plus, winter is coming, and I don't wanna drive a 2WD in snow, ever again.

I need a drink.

 

[kastein]

apparently I was wrong about the axle the Dakota has :dunce: had Rams on the brain after looking through CL listings for parts-donor ones for so long.

You mentioned a *while* ago, it probably had the 29spline, and that enforces what the guy said, so let's go with that.

yup. In a 99, it's almost certain. The only way it could be 27 spline is if the vehicle was crashed or otherwise badly damaged and someone threw in a 27 spline from 1996.0 or earlier as a replacement. So you can damn near count on it being 29 spline. I'd trust a 29 spline 8.25 up to 33s with severe abuse unlocked, 35s with mild abuse unlocked, 33s with mild abuse locked, and 35s with severe abuse locked if you put alloys in it. Others might go even further, I just don't like the risk of breaking shafts. Hell, I beat the bag off my 27 spline 8.25 unlocked on 33s and did nothing to it, it just stretched my U-bolts, battered the spring perches, and wrecked the leaf springs.

Since it's not a D35, would that affect the shaft, other than spline count?

No driveshaft differences, the only differences are the axleshafts themselves, the spider gears, and the differential carrier.

Do they both have the 3.55 ration, dealing with same torque from the shaft? What should I keep in mind regarding the shaft, taking this new find in consideration?

yes, yes, not much. Doesn't really affect driveshaft choices at all, just axleshaft/carrier/spider gear and tire size choices. As long as it's on 33s and below (or even higher, see above) you really don't care how many splines an 8.25 has in it, from my experience.

Also, I'm getting fed up with waiting for available voluntary help. Every time I arrange for 2 or 3 buddies to help me, something happens. I can't even fault them, because I lived the same mini-deployment-to-home-to-training-to-deployment cycle. Their time is precious, whereas my time - thanks to govt hiring freeze on intel resources - is suitably devoid of much use aside school books (don't get me started).

So, I am THIS close to accepting taking it to a shop and merely accompany the process as close as I can. Might cost me a pretty penny (from 1000 to 1500), but waiting forever will both cost and achieve zero. Can;'t do it by myself, since I lack the facilities, and well over $2000 in tools which a shop would possess. With the friends, we would have used the base's auto craft shop, rent a lift and jacks for the trans, and spend two afternoons tinkering and cursing. I'm bummed.

The idea would have been to learn and increase and exercise our vocabularies in the four-letter-word range, while having fun. Well, I did SOME reading and research on the minutia, all I am missing is the damned hands on. Assembling a group of volunteers seems precarious, and I have pretty much no buddies around, who are not in the camouflaged life style. I can't simply waste those sweated-for parts, and my babe deserves to be a full fledged Jeep. Plus, winter is coming, and I don't wanna drive a 2WD in snow, ever again.

I need a drink.

That sucks. It's really a driveway project, a lift and a shop would make things really easy but it's totally doable in a driveway. Hell, I managed to do an engine, transmission (2wd auto to 4wd 5-speed standard), 4wd, front axle, rear axle, lift, and driveshaft swap on my MJ working with the jeep parked on my back porch, alone. It took me several days worth of tinkering over the course of several weeks (due to my work schedule) but if I'd been suitably motivated, I could have done it in a single weekend.

 

[Wallyman]

5 pages to detail how you could've sold the 2wd and combined it with some money and bought a 4wd. I Don't like to piss on someones' campfire but there are just SO MANY XJs out there. This has seemed like a LOT of work. especially for what you say is just a DD.

 

[faraiwe]

@kastein

Makes things less complicated, good. Let's see. I got word of a potential date to start the works (provided I can get a f*ing driveshaft, ugh!!). That failing, it's either shop or ad-eternam postponement. Got a lot on the plate, right now. I know, shouldn't let life get in the way of Jeep, but hey...

@Wallyman

Yes, I know. See, in terms of pure symbolic Logic, "love" can't be quite differentiated from "blackmail", and so on. I simply LIKE this ride. It's been with me through thick, thin, and then some. Might chalk that to me being an idiot who doesn't quit over obstacles, dunno.

--

Mistake me not, this WILL be done. It's just a matter of when and how. I shouldn't bitch too hard. Been going through a rough patch of circumstances lately, but it does not justify whining. Sorry for the outburst last time, thanks for putting up with me, guys.

 

[faraiwe]

Just FTR!

@kastein - Guess what. Found the part. No dents, too! :shock: :yelclap::woohoo:

Went with a buddy to seek a non-related part for my WJ (trim), and a few parts for his vehicle... Spotted a same-year XJ, noticed there weren't many signs of forklift abuse, crawled underneath - what could it hurt, right? - for a second and WHAM! There it was. It smiled at me, I smiled back, birds chirped, butterflies fluttered, we took a long walk in the beach, had some brüt with strawberries, both families met... love at first grease.

It now rests along the other parts, standing by for the process. It's been a minute, time to get this shtick done, one way or the other.

Been polling potential idio... volunteers amongst friends, and they all seem either deployed, or too darn busy. It seems shop it is. Any idea of a trustworthy shop around this area ( Bel Air/Aberdeen MD) ?

 

[Tacedaddy]

5 pages to detail how you could've sold the 2wd and combined it with some money and bought a 4wd. I Don't like to piss on someones' campfire but there are just SO MANY XJs out there. This has seemed like a LOT of work. especially for what you say is just a DD.

i feel the same way.. i just wasted my life reading this whole thing... PS instead of stupid part numbers all you needed to do was post a picture of the rear-end (THE ENTIRE REAR END) and almost everyone would have told you it was an 8.25

 

[kastein]

Just FTR!

@kastein - Guess what. Found the part. No dents, too! :shock: :yelclap::woohoo:

Went with a buddy to seek a non-related part for my WJ (trim), and a few parts for his vehicle... Spotted a same-year XJ, noticed there weren't many signs of forklift abuse, crawled underneath - what could it hurt, right? - for a second and WHAM! There it was. It smiled at me, I smiled back, birds chirped, butterflies fluttered, we took a long walk in the beach, had some brüt with strawberries, both families met... love at first grease.

It now rests along the other parts, standing by for the process. It's been a minute, time to get this shtick done, one way or the other.

Been polling potential idio... volunteers amongst friends, and they all seem either deployed, or too darn busy. It seems shop it is. Any idea of a trustworthy shop around this area ( Bel Air/Aberdeen MD) ?

Awesome!

I have no shop recommendations, but I may end up working down in that area 50% or so of my time in the near future. If I end up down there, I'm down for a wrenching party. No guarantees though, I haven't gotten hired yet.

 

[faraiwe]

i feel the same way.. i just wasted my life reading this whole thing... PS instead of stupid part numbers all you needed to do was post a picture of the rear-end (THE ENTIRE REAR END) and almost everyone would have told you it was an 8.25

Thankfully, reading it is facultative, isn't it? Land of the free, home of the... bored? Everyone's entitled to an opinion and the BEST thing about an opinion is that no one has to care about it.

Have a good one, and don't bother to call, my people will call you...

@kasten

Hey, yeah, I'm pleasantly surprised to find a part that is in decent (mind the OCD) shape. More than a shop, proper, I was originally thinking of just getting an extra pair of hands who has been there before. Avoid the eventual pitfalls, so to speak. I'd be extra-freaking happy with a cherry on top to get the hands-on advice, if you're ever around these parts. :worship:

 

[1975Ironhead]

I have a '98 xj 4wheel drive that is totaled and would be a perfect donor. Has everything you would need, axles, suspension......ect.

 

[cz94xj]

Would that 98 jeep you have be compatible with my 94 xj ? If so I would like to take the parts off your hands !!!!

 

[cz94xj]

I have a '98 xj 4wheel drive that is totaled and would be a perfect donor. Has everything you would need, axles, suspension......ect.

I would like to know if I can use the parts on my 94 xj. Cuse I keep seeing that its a bit diffrent let me now because I'm really interested!!!!!