Sad front differential??

[Gdsmith07]

Well I was planning on getting back under the Yukon today but seems I’ve been called back into the office. Which means ill
Probably be a few days out until I get back under the rig.

Still wanting to get this sorted before fall/winter. Which means I will still be very active on this thread.

I was thinking of getting a a donor front and rear Axel and swapping the gears/rebuilding them myself.

I’m not a differential guy, but I’d like to be hahahaha what’s everyone’s thoughts on that who have done these IFS rebuilds in the past?? Anyway to beef up the 8.25 ?

From what I’ve been able to tell of the 8.25 isn’t that it’s weak but that it’s lacking the ability to add a locker to the front. And that the biggest draw back as always in the cv shafts. I was thinking of ordering some extended travel shafts just to give the suspension that extra bit of cushion or maneuvering.

Is it worth going to the 9.25? How difficult is that swap? I had seen some videos and posts from years ago where people did some housing trimming and such and just adjusted for yoke and drive shaft length. Idk from what I have uncovered the center pumpkin isn’t much stronger but the housing is steel and the cv’s are a little better in the HD form and you have the ability to add a locker.

Hahaha im someone will chime in on this

 

[PatDTN]

My tires need replaced, I wouldn’t say they’re “trash” but they could
Be replaced for sure. Where I am there is no balancing machine so I couldn’t tell you if they’re out of balance but what I can tell you is there is no speed limit on the roads that do exist that is above 40MPH and with the amount of road wash and potholes im
Usually doing 25 and under so I’ve always been under the assumption that I’ve even doing low enough speeds for wheel balance to not make a drastic effect to performance. That may be an entirely wrong thought idk. But I don’t have a way to baalnce the tires. The tires I was going to order I was also going to order a new set of rims and have them shipped balanced.

My 4 other 4WD/AWD vehicles here have no issues and I’ve never balanced the tires on either of them including new tires I’ve put on.

But I’ll be able to rile
Tires out as well here shortly. Unfortunately there is no normal
Tire shop to go to everything has to be flown/shipped in.

I didn't mention balance so maybe you were responding to someone else?

To the question of throwing an ABS light; mine did not. I don't know how different but remember mine is NNBS or GMT900.

I was talking about a possible large difference in rolling diameter. I guess an easy way to check would be to park on a flat level road and chalk the sidewall as close to exactly at the bottom as you can then roll in a straight line as far as you reasonably can and see if the chalk marks are all clocked the same.

 

[Gdsmith07]

I didn't mention balance so maybe you were responding to someone else?

To the question of throwing an ABS light; mine did not. I don't know how different but remember mine is NNBS or GMT900.

I was talking about a possible large difference in rolling diameter. I guess an easy way to check would be to park on a flat level road and chalk the sidewall as close to exactly at the bottom as you can then roll in a straight line as far as you reasonably can and see if the chalk marks are all clocked the same.

Was just working through the possibility of tires. Was ruling out the ability of balancing tires is all!

I could give it a wear pattern check for sure. Never hurts to run with an idea.

 

[Gdsmith07]

What’s going on everyone! I’ve been away for a while but I was doing 14 hour days 7 days a week since June!

So to give an update on the Yukon. I climbed under the SUV and played with the front yolk to see what it felt like. Turning wise it didn’t seem terrible it had a little bit of a noise to it though not a a very faint pop is how I would describe it. Very very faint. It does however have some back and forth wiggle, I guess you would call it slop. Where I can move the yolk side to side and feel it kind of engage but there’s a dead zone.

Well with that I figured the diff was either on its way out or had killed some teeth. It’s just enough slop on the rotational it makes me uncomfortable.

If the vin decode I did correctly it shows my gears were 3.43’s. So like any man I went ahead and picked up a front a rear differential that had 4.10’s under it from a donor rig.

Currently installing the new units. Pretty excited to run 4.10’s with the little 4.8 should make a world of difference. Also itll
Be nice to finally have decent 4WD. I spun the yolk on the donor unit and no loose feeling no dead space in the rotational movement where it feels like it isn’t grabbing then does. It feels smooth and good. Hopefully it solves a lot of my problems. May crack the old one open and see if there was anything going on for sure!

Also eventually going to be installing a Yukon locker in the rear! Once this is done I can start getting back to the aftermarket play parts!!

Ill keep you guys posted on what exactly if anything was trashed in the OEM front diff!

 

[rockola1971]

What’s going on everyone! I’ve been away for a while but I was doing 14 hour days 7 days a week since June!

So to give an update on the Yukon. I climbed under the SUV and played with the front yolk to see what it felt like. Turning wise it didn’t seem terrible it had a little bit of a noise to it though not a a very faint pop is how I would describe it. Very very faint. It does however have some back and forth wiggle, I guess you would call it slop. Where I can move the yolk side to side and feel it kind of engage but there’s a dead zone.

Well with that I figured the diff was either on its way out or had killed some teeth. It’s just enough slop on the rotational it makes me uncomfortable.

If the vin decode I did correctly it shows my gears were 3.43’s. So like any man I went ahead and picked up a front a rear differential that had 4.10’s under it from a donor rig.

Currently installing the new units. Pretty excited to run 4.10’s with the little 4.8 should make a world of difference. Also itll
Be nice to finally have decent 4WD. I spun the yolk on the donor unit and no loose feeling no dead space in the rotational movement where it feels like it isn’t grabbing then does. It feels smooth and good. Hopefully it solves a lot of my problems. May crack the old one open and see if there was anything going on for sure!

Also eventually going to be installing a Yukon locker in the rear! Once this is done I can start getting back to the aftermarket play parts!!

Ill keep you guys posted on what exactly if anything was trashed in the OEM front diff!

I hope you arent planning on running down the road and engaging the 4WD with 4.10 gears in the front and 3.43 gears in the rear? If you do, can you do a video with a GoPro mounted underneath the chassis so we can witness the carnage?

 

[PatDTN]

I hope you arent planning on running down the road and engaging the 4WD with 4.10 gears in the front and 3.43 gears in the rear? If you do, can you do a video with a GoPro mounted underneath the chassis so we can witness the carnage?

He did say front AND rear.

 

[Gdsmith07]

I hope you arent planning on running down the road and engaging the 4WD with 4.10 gears in the front and 3.43 gears in the rear? If you do, can you do a video with a GoPro mounted underneath the chassis so we can witness the carnage?

Yeah unfortunately I won’t be able to do that. I changed the front and rear units out. Pulling it out of the shop today to see how it rides.

 

[mountie]

Man-o-man.... I partially read these posts.......
I bought my '05 Yukon XL 4wd 'select able' about 5 years ago..... Everything seems very good......
No warning lights, etc........
I have NEVER engaged the 4 wd ...ever..... ( Haven't needed to)......
167,000 miles. Should I service it ?? Is it just a drain & fill ??
I am thinking of preventative maintenance.....??

 

[Gdsmith07]

Swapped the front and rear ends out and it runs like a dream. Safe to say the front end was going. Kept the unit to be able to tear into and see what exactly happened. But as far as my 4WD goes it’s working perfect!

 

[Gdsmith07]

Man-o-man.... I partially read these posts.......
I bought my '05 Yukon XL 4wd 'select able' about 5 years ago..... Everything seems very good......
No warning lights, etc........
I have NEVER engaged the 4 wd ...ever..... ( Haven't needed to)......
167,000 miles. Should I service it ?? Is it just a drain & fill ??
I am thinking of preventative maintenance.....??

Man so sorry for the super late response!

You can do a service on the transfer case and the diffs. The front differential has a drain plug just drain it and then fill get the spec fluid required for your vehicle. The rear diff, at least on the three GM trucks/SUV’s I’ve owned of these models, you need tp unbolt the rear diff cover drain the fluid and then put a new gasket and fill the diff.

The transfer case you can just drain from the plug and fill with GM’s specific transfer case fluid. I’m sure they sell a variant at the local parts store.

Good luck! If you engage the 4WD you will know very quickly if something is out of place!