Getting my ducks in a row

[NC_IslandRunner]

The few times that I have had the diff cover off my rear end to change the fluid, I bought a new gasket and use a light skim of black RTV on it. As far as I know, it isn't a trouble area.

I use the hard rubber gasket with the ridges, a little gear oil and bolt it up, no issues!

[HARDTRAILZ]

I just use RTV.

[Shdwdrgn]

I was getting dressed to head out and do my axle swap when it occurred to me... with all the flooding going on right now (and more storms approaching today and tomorrow), I just might want to hold off for a week and keep my 4WD operational -- JUST IN CASE. I dunno, something about having to plan ahead, and drive miles around town just to get from one end to the other...

This whole situation is a new thing for me. This month marks 30 years that I've lived in this town, and I've never seen anything like this. I hear about flooding in other towns around the area, but I've never seen it happen here.

Oh yeah, and just to double-check... it IS safe for me to change out the rear axle and drive around for a couple weeks before changing the front, as long as I don't try to engage 4WD, right?

[HARDTRAILZ]

Yup

[Shdwdrgn]

All I can say is ... WOW!

Had some issues getting some of the bolts loosened, then I couldn't get the calipers to collapse while putting everything back together. All in all, 5 1/2 hours were spent getting everything squared away. I took it out for a test drive, and the dash started to panic, flashing lights and warning about the brakes ... "Oh yeah, I forgot to top off the fluid after opening the bleeders" Got that topped off, took it for a ride down a highway with lots of steep hills so I could get a real feel for any changes, and boy are there changes! It just really picks up and goes, even on the up-hill runs. It may only be a 300-rpm difference at highway speed, but it sure makes a difference.

Tomorrow I'll get the computer reprogrammed and see what differences that makes. At the very least, it is (of course) waiting way too long to shift now, so I can at least get that corrected. I'll also make a spot-check on bolt tightness and look for any leaks from the diff. It will likely be a couple weeks before I get to the front diff (wife signed us up for a house-warming party next weekend), but at least now I know the effort is completely worth the time.

I should hitch up that 5000lb trailer now and see how THAT handles

[djthumper]

Nice!

[Shdwdrgn]

Oh by the way... what it the fluid capacity for the 8.6" diff? My old one was 1.8 quarts, but I ended up putting around 2.5 quarts in the new one to top it off. Really glad I keep an extra quart on hand!

[Shdwdrgn]

So for all you folks that have 4.10 gears, does anyone have HPTuners and would be willing to send me a copy of your file when doing a 'read entire'? I was reading that this can capture the information needed for rewriting the gear ratio, I just need to get ahold of the file from someone so I can actually try it.

[Shdwdrgn]

The guy that was going to help with my diff swap is sick today, so we're going to do it tomorrow. I figured I would start trying to clean up my workbench, and discovered an extra package that had been shipped with my front diff... Looks like part of the axle, and since I assumed I was just going to re-use my current axle parts -- but after reading through threads this week, something caught my eye. I unwrapped the saran wrap, and couldn't believe it... they actually shipped the 4x4 disconnect along with the front diff! So I have on my workbench a complete disconnect with only 65k on it, and this gives me a chance to throw in all my rebuild parts and have this piece completely ready to go for tomorrow.

So my big question... the replacement part is from a 2007 SS. Judging by pictures, it is exactly the same, but does anyone know for sure? Anyone have a cross-reference that can tell me if its an exact match for my 2004 TB SWB?

[EDIT] SCRATCH THAT... I opened it up, this came from the AWD version. It has the sleeve, as shown in the last image on http://www.offroadtb.com/articles/tech-docs/front-axle-4wd-disconnect/, rather than the shift forks. Ah well, so much for getting ahead. At least I have some spare parts on hand now, in case there are any mechanical defects with the one in my truck...

[Regulator1175]

You want the sleeve! forget rebuilding it with the same parts, use the sleeve and eliminate future problems within the disconnect.

All the cool kids are using it!

[Shdwdrgn]

Sure sure... all the cool kids that don't mind the reduced gas mileage! But hey, at least I have the parts on hand - "just in case"

[TBYODA]

Sure sure... all the cool kids that don't mind the reduced gas mileage! But hey, at least I have the parts on hand - "just in case"

IIRC JD did that mod and did not see a reduction in MPG.

[Regulator1175]

I have it as well and it does not affect anything. All that happens is that the passenger tire is locked in with the intermediate shaft. The front diff is still disengaged from the shaft until you put it into 4 wheel drive. Having the sleeve in will not affect drive-ability at all.

If not I am certain you will find a buyer for it!

[TBYODA]

Sure sure... all the cool kids that don't mind the reduced gas mileage! But hey, at least I have the parts on hand - "just in case"

If you don't want the Sleeve pm me.

[Shdwdrgn]

Apparently there is a line forming. Maybe I should start taking bids? Sure wish I could get that kind of response in trying to sell my old rear axle.

So I don't get it... Does this sleeve do the same thing as having my dash switch in the A4WD position (which I thought was supposed to be BAD to use)? Does it affect turning radius in any way? The only off-roading I do is light by you guys' standards, however I do like having good control when the heavy snow hits. I have no plans for lifting my truck, other than maybe adding an inch in front to level it out. So tell me, why all the excitement over the sleeve, and what benefits are you guys getting from using one?

(FYI, I do like the idea of fewer components, less that can go wrong, but I don't want it to be a trade-off for additional wear on the drivetrain)

[ErikSS]

Personally, I think you should get a the ATP disconnect and Doorman actuator like I have. Those who've spent the $ on them seem happy.

[Regulator1175]

Apparently there is a line forming. Maybe I should start taking bids? Sure wish I could get that kind of response in trying to sell my old rear axle.

So I don't get it... Does this sleeve do the same thing as having my dash switch in the A4WD position (which I thought was supposed to be BAD to use)? Does it affect turning radius in any way? The only off-roading I do is light by you guys' standards, however I do like having good control when the heavy snow hits. I have no plans for lifting my truck, other than maybe adding an inch in front to level it out. So tell me, why all the excitement over the sleeve, and what benefits are you guys getting from using one?

(FYI, I do like the idea of fewer components, less that can go wrong, but I don't want it to be a trade-off for additional wear on the drivetrain)

From my understanding, the A4WD has the front diff engaged and engages the spline disconnect when it senses wheel slip. This action is what causes failures in the disconnect.

Honestly, for your application I don't see any reason to use it. You will benefit from selling it and recover some of your money from your upgrades. The benefit for us, the hard wheelers, is that it takes the fork out of the equation which can break in heavy abuse situations.

[dvanbramer88]

FWIW, it is my understanding that the sleeve reduces driveline wear and tear. Instead of the CV torquing down on the outer bearing and outer gear and oil seal from the lift, the AWD sleeve is supported by all 3 bearings all the time spreading the load and keeping everything inline.

Also, i thought the A4WD engaged the front end (disconnect) and when wheels slipped, it quickly engages the Transfer case/front differential via clutches. That's why guys with finicky disconnects, while wheeling, go into A4WD instead of 2WD, when they want 2WD for a short period of time with the intention of going back to 4WD when they get to the next trail/obstacle. It keeps the front disconnect "locked up"

IIRC, MDB did/does that on TECORE.

[Trail X]

Correct Dave.

For someone at stock height, however, the awd sleeve will not be as much of a benefit. The disconnect has its biggest issues when the cv shaft is at an angle, from lifting the front suspension. Stock height the disconnect tends to wear less, and that is the big thing that the sleeve helps prevent - wear inside the disconnect. However, yes, it does wear the front pinion seal more..

[ErikSS]

FWIW, it is my understanding that the sleeve reduces driveline wear and tear. .

It is obviously easier on the disconnect, but not the differential. As with most changes in driveline, you gain some and you loose some. I still like the ability to release the front axle with the disconnect. I will probalby change my mind after I break couple parts, but so far so good. I intend to do moderate offroading though.