Replacing front diff

Deb'nKJ

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Pt. 1 – remove front drive shaft:

OK so here’s where I’m at, unbolted, rear flange disconnected, front flanges move freely against each other – but won’t fully separate because there’s not enough room for the shaft to go back that far. Have I done something wrong? If not, what’s the answer?

Fully accept might have to remove exhaust, which should provide some wriggle room, (& already mentioned elsewhere that’s on the agenda, anyway) – but what’s the trick unplugging the up-stream sensor? I can touch the connector but not hold it to pull it apart & certainly can’t get a screwdriver to it to unlock it.
 

JeepJeepster

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What are you working on?

On my 04, I was able to push the rear of the shaft (tcase end) up above the tcase and towards the rear of the Jeep so I could get the front out and down. Then it came right out.

From what I understand, some years are more difficult than others. No idea what years are more/less difficult.
 

JRB

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Same way on my 2007 as JeepJeepster, hopefully it works for yours as well Deb'n!
 

tommudd

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yES GET REAR OUT A BIT, THEN PUSH IT UPWARDS WHILE PUSHING THE DRIVESHAFT SOMEWHEAT SHORTER THEN FRONT WILL COME DOWN OUT AND REMOVE
 

Deb'nKJ

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Well I thought I'd tried every which way but always came up against not being able to get past the TC flange but maybe I didn't try up & over. So thanks for that, it'll be what I'll be concentrating on next Saturday: almost looking forward to it - so you may have detected a distinct change of attitude.
Ironically, with the driveshaft out of the way I might just be in a better position to disconnect the up-stream oxygen sensor, but just so I'm prepared - what's the trick here?
 

J.C.

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Well I thought I'd tried every which way but always came up against not being able to get past the TC flange but maybe I didn't try up & over. So thanks for that, it'll be what I'll be concentrating on next Saturday: almost looking forward to it - so you may have detected a distinct change of attitude.
Ironically, with the driveshaft out of the way I might just be in a better position to disconnect the up-stream oxygen sensor, but just so I'm prepared - what's the trick here?
I have just finished replacing the front propeller shaft on my 2007 KJ CRD.

If you have a V6, then the exhaust joint probably has to be unbolted.

This section from a Service Manual has the description headings reversed.
The first section is actually showing the exhaust for the V6.

Once the 6 bolts from each CV have been removed, the rear (Transfer Case) end is first to be taken out by compressing the shaft spline towards the front and sliding the rear CV up and off the flange. The shaft can then be dragged back a bit with the rear CV sliding above the flange, but it tends get hooked so will need to be wriggled a bit. This allows the front CV to be removed from the flange on the front diff.

NOTE:
Check that the front output shaft (flange) on the Transfer Case does not have lateral (up/down) movement in the bearings, as this is a source of vibrations, too.



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J.C.

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Well I thought I'd tried every which way but always came up against not being able to get past the TC flange but maybe I didn't try up & over. So thanks for that, it'll be what I'll be concentrating on next Saturday: almost looking forward to it - so you may have detected a distinct change of attitude.
Ironically, with the driveshaft out of the way I might just be in a better position to disconnect the up-stream oxygen sensor, but just so I'm prepared - what's the trick here?
I've come into this thread a bit late and am wondering why are you replacing the front diff?
 

Deb'nKJ

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I have just finished replacing the front propeller shaft on my 2007 KJ CRD.

If you have a V6, then the exhaust joint probably has to be unbolted.

Yes I do & yes I was resigned to that (the cats are universal stainless steel ones and the welded joints are far from gas tight; something more easily remedied on the bench)

This section from a Service Manual has the description headings reversed.
The first section is actually showing the exhaust for the V6.
So far, I've found the SM well up to Haynes standards
Once the 6 bolts from each CV have been removed, the rear (Transfer Case) end is first to be taken out by compressing the shaft spline towards the front and sliding the rear CV up and off the flange. The shaft can then be dragged back a bit with the rear CV sliding above the flange, but it tends get hooked so will need to be wriggled a bit. This allows the front CV to be removed from the flange on the front diff.
That accords with what TM suggested (almost the opposite of what the SM says) so that'll be my approach on Saturday
NOTE:
Check that the front output shaft (flange) on the Transfer Case does not have lateral (up/down) movement in the bearings, as this is a source of vibrations, too.
Vibration's not an issue, but thanks for the thought.
Oh, & I'm having to replace the diff 'cos I cracked an axle tube :
 

Deb'nKJ

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Fist major obstacle (for me) overcome & the front drive shaft's now behind the back seat. Next was an unexpected diversion, because the rear hatch/window wouldn't latch. As it was starting to rain I adjourned for coffee, which inspired me to temporarily reconnect the battery, used the fob to lock the doors then, standing behind the Jeep, unlock them & - lo & behold, the latch snapped open.
So, problem solved, back to the job in hand. My intention was to remove the exhaust next (so I can get it welded) but must make refitting the driveshaft easier but decided to tackle those diff mounting bolts that won't draw out because they'd hit the lower control arms. My thinking was to undo the nuts & withdraw the bolts enough the cut them off under the heads more easily. Will then have a pattern to shop for replacements while I have a week off. Unfortunately, I don't have a suitable wrench down here in Devon, as my main tool box is up in London, so that will have to wait. Meanwhile, can someone tell me what size those bolts are?
 

tommudd

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YES that is the way you do it, been saying all along
Loosen the two forward cut them off and then when reinstalling just install the bolts the way they should of been from the factory
No loosing the LCAs or anything , super simple
 

Deb'nKJ

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Obviously the diff's fitted before the control arms so that's what's easiest on the assembly line - & who cares what problems it causes for others further down the road.

Although I can't do that that job this week, it is an ideal opportunity to get the replacement bolts, but I'll work something out.
 
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