Rear axle delete

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I have 2005 Hyundai Tucson (2.7L MPFI V6)
Purchased new and in very good shape except the whirring sound from rear diff.
Currently diagnosed with a "rear diff" issue.

Background info:
  1. Car is 4WD
  2. 4WD has a 4WD-Lock switch. Only for under 23 mph.
  3. Open rear diff
  4. if rear wheel slip is detected, power is temporarily transferred to rear.
  5. Basically car is in FWD %99.9 of the time based on our driving habits and needs.

I've noticed #4 twice in 17 years. I think a little traction light blinks if slip is detected. Used #2 only a few times ...

Noise issue:
I'm told it's not the bearings and the noise is coming from rear diff. Friend and I will do our own test ... but lets go with the rear diff issue for now.

I'm told anywhere from $1500 to $4500 ... and no one wants to work on it. I guess they are not hungry and the business must be good and they keep referring me to other trans outfits and the trans shops say take it to the dealer ...


big question for the experts:
please refer to #5

based on #5, I figured why not just get rid of the rear diff and other moving parts, etc.

can we just do a rear axle or rear diff delete and have a front wheel drive car? That's where the car spends its time %99+

the car has been great with 228K miles. we are the original owner and besides tires, 2 or 3 batteries, timing belt/water pump and spark plugs at 140K miles and couple of hoses here and there, nothing else has been done to the car. Burns ZERO oil and engine sounds very smooth ... That translates into the car maybe ready for a lot of other repairs and/or maintenance issues. Not going to happen! lol
I'm not going down the road of spending any major $ on this car and also don't have time for future headaches ... I don't want a $3500 rear diff bill. imho, the car is too old for me to start fixing this or that.

Basically 228K miles and 17 years old. It's done a great service and will buy it again. However it's either Rear Axle (rear diff) delete or nothing.

can you do a delete and what are other implications if any?
if it's possible, then I'll try to find a shop to do the work. I asked one rear diff shop and they neither wanted to fix nor do the delete and told me to go to the dealer.
I think it should be a very fun project for any shop!

Thanks for your help and comments!
 
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I just found a whole diff on eBay for $255.00.

Deleting the rear diff will likely be a ****. Do the rear half shafts keep the wheel bearings together? If so, you'd have to take the cv apart and reinsert it or buy 2wd bearings. There could be a tone ring on the rear diff too.

I would just find a reasonable rear diff, replace, and motor on.
 

OilUzer

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@ctechbob
I will watch the video and update.

@Zaedock
The rear diff (center piece) connects to cv looking parts not far from the center and near the wheels, there is another cv for total of 4. I think because it's independent suspension it needs 2 but why does it have 4? idk
 

OilUzer

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Make sure there is oil in it and drive it. It will either delete itself of outlast the car.

Rear diff fluid looks very clean.
I changed it not too long (20K miles?) ago.

I'm worried if something seized in one wheel or somewhere else possibly on some slippery roads (rain, ice, snow) or even dry road and I get into an accident ...
 

OilUzer

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Why can't you just remove the rear driveshaft?

That's a possibility I assume but the noise is coming from the rear and even in 2WD, the rear diff is turning (by wheels turning) and it turns the drive shaft which goes to the front transfer case. Under normal conditions , the drive shaft is free spinning and when slip is detected, the transfer case will engage and transfer power to rear tire. i.e. No longer it's free spinning...

Pardon the non-technical language :)
 
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If it’s not a solid rear axle but a rear diff with half shafts going to it, you could probanly drop the half shafts, and-or split the CV joints if you need to. this is assuming of course that it is a 100% FWD vehicle with rear assist, not driven thru a center differenrial.

youd have to examine the drive shaft however, because the hub or flange that turns it from the front PTU may slip out without having the driveshaft in place. That would be bad.
 

OilUzer

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If it’s not a solid rear axle but a rear diff with half shafts going to it, you could probanly drop the half shafts, and-or split the CV joints if you need to. this is assuming of course that it is a 100% FWD vehicle with rear assist, not driven thru a center differenrial.

youd have to examine the drive shaft however, because the hub or flange that turns it from the front PTU may slip out without having the driveshaft in place. That would be bad.

It does not have a solid rear axle like my truck does.

This car has independent suspension and I see a cv joint at each wheel and 2 other CVs (1 on each side of rear diff) connecting the two half shafts? Basically I see 4 CVs on the rear axle.

This car is NOT an AWD. Pretty sure of that but has a 4WD lock button for low speeds under 23 mph.

Pretty sure I've been told more than once it is a FWD for most parts unless when "slip" has been detected and then the rear (via transfer case) will temporarily engage ... but I will double check.

also I'm not a mechanic. I figured if it's mainly a FWD, then let's get rid of the rear drive mechanism ... and make it a real FWD.
Not sure if it's a good idea or it is feasible or if cheaper than repairing ...

Buying a used rear axle is an option as suggested but who knows what shape they are in.

I thought it may be easier and much cheaper to remove parts but the guy at the rear axle shop (referred to me by a trans/front axle shop) looked kind of puzzled or surprised when I asked if he can do the delete. Had a feeling it's not a common job or request by the look on his face. :alien:
 
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  1. Car is 4WD
  2. 4WD has a 4WD-Lock switch. Only for under 23 mph.
  3. Open rear diff
  4. if rear front wheel slip is detected, power is temporarily transferred to rear.
  5. Basically car is in FWD %99.9 of the time based on our driving habits and needs.

I fixed that for you.

No offense dude, but this idea is pretty stupid. You're vastly underestimating
the effort required to perform this mod and that just one of several reasons
why I bet you'll never accomplish this.
 
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also I'm not a mechanic. I figured if it's mainly a FWD, then let's get rid of the rear drive mechanism ... and make it a real FWD.
Not sure if it's a good idea or it is feasible or if cheaper than repairing ...
Have done this on a Saturn Vue, removed the rear driveshaft because of a bad driveshaft support bearing. Drove around fine for months. Didn't remove the axle shafts though. Wouldn't make much sense to spend that much money on a 17 year old Hyundai to fix something you rarely use.
 

gathermewool

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I’d personally love with the whirring sound until it got bad enough to definitively pin point. How do you know it’s not a bearing or maybe even the tires? I’d get a second opinion and make sure they check with it on a body lift so they can use a stethoscope to find the culprit.
 

OilUzer

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Then also remove the two drive axles. Problem solved but you may have to take out the outer CV joint housings and bolt them back in the hubs.

You are right.

remove the drive shaft. The rear axle/diff can stay or go. TBD
There is slip yoke? or u-joint right after the transfer case to disconnect the drive shaft. I think there is also one right before the rear diff but not sure. TBD
Then disconnect the CVs near the wheel (that might be the biggest challenge) then the whole rear drive mechanism would be offline.

@Asterix has good idea. I may try another local rear axle shop then go to a smaller shop. It should be a fun project and send it to junkyard if it didn't work. Maybe it won't be as simple as we think but we'll find out.

@gathermewool
Friend and I are going to lift the car and confirm but one shop did a body lift and stethoscope and said "rear diff" issues. Brakes, tires and bearings were fine according to them. I'm not sure if the noise was from the center diff or the other 4 CVs that connect the rear half shafts. Hoping friend and I can pinpoint the source.
 
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