Has anyone gone back to a live axle from a IRS?

[danasc]

Well never mind - (Was wanting info on going to a rear solid axle and change the IRS in our explorer) just got back under it and took a good look - IRS frame is very different - but anyone know if a tbird Differential might fit - the old ones If I remember , were Iron I really don't want to fix a rear end once a year because of a cheap pot metal housing- and I know about the 31 splines - I have that stuff laying around in here - 2003 4 door explorer XLT 4WD, Towing Pkg - 4.0 , I'm not sure if it needs a rear end yet as the tires are making so much noise , new ones ordered, but all the wheel bearings are not a week old - and I mean all 4 wheels - just has a noise I don't like -

 

[shadowless127]

IIRC the 03 Cobra IRS is plug and play.

 

[kermitstang86]

IIRC the 03 Cobra IRS is plug and play.

Are the 03 04 Cobras a 31 spline setup?

 

[CDW6212R]

Are the 03 04 Cobras a 31 spline setup?

Yes.

 

[CDW6212R]

IIRC the 03 Cobra IRS is plug and play.

Do you mean that the Cobra differential housing will swap with the 02-05 Explorer housing? I've been looking for a Cobra IRS for a reasonable price.

 

[jd4242]

Watching. .interested in this info as well,really havent heard of the ifs breaking though. ...i have the 03 aviator though, with 3.55 open i have a spare set of 3.73 LS from a 8.8 explorer,would the whole thing fit in the ifs?? Carrier and gears by chance??

 

[jd4242]

The diff, and gears are a direct swap to any 31 spline 8.8 housing.

The diff?? Mean carrier?

The gears and carrier are out of a 98 explorer soild rear axle..the 03 aviator is a IRS

The OP said something about different splines?? Is the 03 IRS the same spline count as the 32 8.8 solid axle. .

OP ...What normally breaks on the IRS

 

[boominXplorer]

Carriers between the two are slightly different. The side gears that accept c-clips are a different depth and don't hold the axle in tight.

 

[jd4242]

Carriers between the two are slightly different. The side gears that accept c-clips are a different depth and don't hold the axle in tight.

So no LS/carrier swap then..how about the gears ?

 

[CDW6212R]

Carriers between the two are slightly different. The side gears that accept c-clips are a different depth and don't hold the axle in tight.

Okay, I hadn't heard of that. I thought all 8.8 differentials would swap in all 8.8 housings. I'll accept that and delete my other post. Thanks for the information.

 

[TTSport15]

Check out FB there is a CobraParts ID on thr a lot of good stuff ...

 

[jd4242]

Check out FB there is a CobraParts ID on thr a lot of good stuff ...

Whats the benifits of going to the cobra irs diff

 

[TTSport15]

Whats the benifits of going to the cobra irs

I no the ride between an 99-04 Gt compared to the Cobra is nite n day

 

[boominXplorer]

Let me be a little more clear. You can swap the following parts irs to solid 8.8. The carriers, clutch packs kits(stock and Ford racing ect) and top and bottom spider gears. The only difference is the side spider gears.

 

[CDW6212R]

So the side gears are made for the IRS axles, which don't use c-clips right? It's like the front of our trucks that use the CV axles with circlips, and the shallow groove in the differential is unique versus other D35 versions. I can visualize that.

 

[Mr. Truckles]

I've done a few different things on mine. The first time I blew up my rear (D4 3.73LS) I rebuilt it with the ring, pinion, carrier, spiders, and side gears from a solid D4 8.8. I personally didn't notice any significant problem with the side gears, and drove it for about 35k miles before putting in my locker, but then again I didn't really check it. I do remember noticing that one of my new seals never seemed so seat properly and that would probably explain why.

It should be noted that at least the LS carrier (at least the one I used) from the solid axle was the older style one which has a slightly different shape around where the clutch pack is housed, but it fits all the same.

When I installed my spartan locker I used an open carrier from a crown vic 8.8 but kept the ring gear from the previously swapped in unit. This has also been working well for around 10-15k miles so far.

 

[CDW6212R]

From what's pointed out above, the side gears have a shallower area in them from the IRS carriers, which is for the axle circlips. That means that the normal side gears would work in the IRS, the circlips would engage the normal ledge of the non-IRS side gears. It sounds like the IRS axles might be harder to remove from the "normal" side gears.

A problem should be trying to use the IRS carrier in a non-IRS housing. Those IRS side gears won't have the required ledge/pocket for the c-clips to fit into. I haven't seen the IRS side gears, so I am curious about what they are shaped like on the inside inner end. Someone should post a picture of the IRS side gears.

 

[Mr. Truckles]

From what's pointed out above, the side gears have a shallower area in them from the IRS carriers, which is for the axle circlips. That means that the normal side gears would work in the IRS, the circlips would engage the normal ledge of the non-IRS side gears. It sounds like the IRS axles might be harder to remove from the "normal" side gears.

A problem should be trying to use the IRS carrier in a non-IRS housing. Those IRS side gears won't have the required ledge/pocket for the c-clips to fit into. I haven't seen the IRS side gears, so I am curious about what they are shaped like on the inside inner end. Someone should post a picture of the IRS side gears.

I'm not sure if I still have mine, but if I do I can post a picture later. I agree 100% they did go in but were definitely more difficult to remove. Now that I recall, when I did my locker I could only get one axle out so I needed to separate one of the axles at the tripod joint and remove the shaft with the case open on my bench.

 

[CDW6212R]

I'd guess that the IRS side gear has a beveled edge where the circlip has to pass or engage, to make it easier to remove, but still have resistance. The c-clip version will be a 90* edge, to hold the c-clip solidly.