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How much power will a stock 8.8" differential take?




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It should take quite a bit of power. I have mine with 36's and it seems to be holding up just fine.
 












So what would be the problem if I have rotational "slop" in the driveshaft--

meaning, the driveshaft and yoke turn a bit before the diffy does--

It seems there is slop between either the pinion and ring, or the ring (carrier) is loose.

(cousin Eddie voice) I dunno:dunno:
 






sure its not the pinion bearing? Have it checked or check the torque on it for play

search for this, I believe you can upgrade to a 9" style pinion bearing and yoke setup...I think Rick has
 






In a drag racing application, I have seen the 8.8" 31 spline rear-ends live in a 2800 lb car, putting out 550hp N/A, and 700 on the bottle....

I don't know if I'm brave enough to put THAT much power to one, but it CAN be done...

Ryan
 






Slop in rear driveline could be a number of things
-Excessive backlash between the ring and pinion
-Play in the spyder gears by being worn over time
-Worn clutch packs in the L/S models
-U-joints in the driveshaft



I grenaded a 4.10 ring gear 3 weeks ago. First time I have done that. Now I'm workin with some 4.88s. I can bark 35s good. Planning on a track run soon.
 






sure its not the pinion bearing? Have it checked or check the torque on it for play

search for this, I believe you can upgrade to a 9" style pinion bearing and yoke setup...I think Rick has

Thanks--that makes sense-as if the pinion isn't tight enough on the ring--

I'll check that!!

umm, does this go for the t case also, or is is supposed to have a bit of slop?

There must be some there also if the driveshaft rotates freely just a bit-understand?
 






Pinion bearing is not really going to cause much slop. More like vibration.
 






Well, this started after the 2wd fun started--
I promise you guys-I haven't lit them up over 20 times though, I usually drive this very carefully.
I replaced the u joints for the clunk-they were fine really.
I wonder if a video would help?
 






Slop in rear driveline could be a number of things
-Excessive backlash between the ring and pinion
-Play in the spyder gears by being worn over time
-Worn clutch packs in the L/S models
-U-joints in the driveshaft



I grenaded a 4.10 ring gear 3 weeks ago. First time I have done that. Now I'm workin with some 4.88s. I can bark 35s good. Planning on a track run soon.

Well, all of those are possibilities--
 






How big is the clunk? Some clunk is OK. There can be slack in the ring and pinion, spider gears, etc. The 4406 case has a little slack too. In park, how much can you twist the rear driveshaft before you get resistance?
 






How big is the clunk? Some clunk is OK. There can be slack in the ring and pinion, spider gears, etc. The 4406 case has a little slack too. In park, how much can you twist the rear driveshaft before you get resistance?

If i was to make it a straight line, I'd say 1/4" -1/2" last i checked it.
 






Stacked tolerences?

Is your truck ideling at the recomended idle setting (I'm assuming thats 347 ci.) If not it could be stacked tolerences. Which means every time a gearing change or power trane components are splined together there is minute clearences at each place that this occurs eventuly all of the tolerences become large enough to pop. Most noted on 4wd with auto trans between drive and reverse. If it is a pinion berring loose you should be able to move the yolk up and down. But if it were a pinion bearing pop would probably be the second thing you notice after the roar coming from the ring and pinion not meshing corectly.
 






Ditto, where is there more rotating play, in the TC or the diff? Hopefully it's just excessive play in the rear, gears and bearings. Climb under it and push/pull on the pinion yoke. It shouldn't move side to side very much at all, same for the transfer case.

How good is the rear fluid, is it high dollar synthetic? Hopefully you just need to do some bearings in the rear end.
 






If i was to make it a straight line, I'd say 1/4" -1/2" last i checked it.

I am pretty sure mine moves at least that much. Do you have any unusual noise or vibrations? Or just a clunk? How high is your idle?
 






Is your truck ideling at the recomended idle setting (I'm assuming thats 347 ci.) If not it could be stacked tolerences. Which means every time a gearing change or power trane components are splined together there is minute clearences at each place that this occurs eventuly all of the tolerences become large enough to pop. Most noted on 4wd with auto trans between drive and reverse. If it is a pinion berring loose you should be able to move the yolk up and down. But if it were a pinion bearing pop would probably be the second thing you notice after the roar coming from the ring and pinion not meshing corectly.

It sounds nice and smooth-just the "clang"

It might be noted that I have a 9" 3000 rpm flash speed converter.while the idle is bumped a bit,it was matched to the camshaft and supposedly these issues were taken care of--
 






Do you have a slip yoke on the driveshaft? If so, take it apart and grease the splines. If the splines on the slip joint get dry it can cause the 'clang' noise.

I don't think mine has any less play then the 1/4" to 1/2" either. It sure seems like a lot when you're under there turning it by hand but between the transmission, transfer case and rear end that isn't that much rotation per piece of hardware.
 



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Do you have a slip yoke on the driveshaft? If so, take it apart and grease the splines. If the splines on the slip joint get dry it can cause the 'clang' noise.

I don't think mine has any less play then the 1/4" to 1/2" either. It sure seems like a lot when you're under there turning it by hand but between the transmission, transfer case and rear end that isn't that much rotation per piece of hardware.
I greased the slip yoke about 10 days ago when I changed the u joints
The clang is definitely from the diffy housing, it sounds kind of like a bell-or like it is from inside--
 






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