Hunter Mike
Well-known member
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- Buick Ownership
- Dark Moon 19 Buick Opel Vauxhall Insignia Country Tourer Regal TourX Essence Estate Avant Wagon
I took the time today to change the factory fill in the PTU unit. For someone who has a lift this is an easy 15 minute job using minimal tools. I did it on my garage floor using ramps and jacks and it took about an hour. Mileage was 15,400, 90% highway.
The PTU uses a ACDelco specific fluid p/n 19351882. It has a list price of over $90USD/quart! The description shows it's a 75w-90 synthetic gear lube with EP additives. I was tempted to use some 75w-90 gear lube I have in the stash but with a new transfer case price of $1k or more plus install I bought the fluid from the dealer. I knew it was pricey so I told my dealer to help me out on the price so I walked out for $55+tax. Several online sellers are close in price but charge a ton for shipping so I was happy with the price.
I drove the car up on my Rhino ramps and then jacked up the rear. Making sure the car was level front to back and left to right I then added jack stands under the rear for extra safety.
The fill plug and drain plug are closest to the right side of the PTU and I found going under the front of the car to be the easiest to get a good view.
Fill:
Drain: (sorry about the angle)
You can see that both are identical and have a 3/8" square drive head and there was plenty of room to fit my 3/8" drive ratchet into both.
First step on any differential change is to make sure you can refill it! Remove the filler plug first, then the drain plug. I estimate the torque was between 15-20lb-ft. I put a clean drain pan underneath so I could get a visual on the fluid. It was a bit darker than new but not horrible.
The drain and fill plugs were identical and both were magnetic. The drain plug on the right has most of the metallic crud on it.
If you have the car on a lift over your head filling is pretty easy but there is limited access. I needs to be pumped up to the PTU. I chose to fill it from the top using 3 feet of 1/4" clear tubing that I ran behind the engine. I bought a new 2oz/60cc syringe from a hardware store from the equine section. If I did it again I would use 3/8" tubing as it was the bottleneck and try to find a bigger syringe. The specified capacity is 0.69qts according to GM. That translates to 22oz. I put 23ish oz. in mine before the fluid was dripping out.
I didn't want to waste any of this precious proprietary fluid and only lost about an ounce in the process.
Let me know if you have any questions.
The PTU uses a ACDelco specific fluid p/n 19351882. It has a list price of over $90USD/quart! The description shows it's a 75w-90 synthetic gear lube with EP additives. I was tempted to use some 75w-90 gear lube I have in the stash but with a new transfer case price of $1k or more plus install I bought the fluid from the dealer. I knew it was pricey so I told my dealer to help me out on the price so I walked out for $55+tax. Several online sellers are close in price but charge a ton for shipping so I was happy with the price.
I drove the car up on my Rhino ramps and then jacked up the rear. Making sure the car was level front to back and left to right I then added jack stands under the rear for extra safety.
The fill plug and drain plug are closest to the right side of the PTU and I found going under the front of the car to be the easiest to get a good view.
Fill:
Drain: (sorry about the angle)
You can see that both are identical and have a 3/8" square drive head and there was plenty of room to fit my 3/8" drive ratchet into both.
First step on any differential change is to make sure you can refill it! Remove the filler plug first, then the drain plug. I estimate the torque was between 15-20lb-ft. I put a clean drain pan underneath so I could get a visual on the fluid. It was a bit darker than new but not horrible.
The drain and fill plugs were identical and both were magnetic. The drain plug on the right has most of the metallic crud on it.
If you have the car on a lift over your head filling is pretty easy but there is limited access. I needs to be pumped up to the PTU. I chose to fill it from the top using 3 feet of 1/4" clear tubing that I ran behind the engine. I bought a new 2oz/60cc syringe from a hardware store from the equine section. If I did it again I would use 3/8" tubing as it was the bottleneck and try to find a bigger syringe. The specified capacity is 0.69qts according to GM. That translates to 22oz. I put 23ish oz. in mine before the fluid was dripping out.
I didn't want to waste any of this precious proprietary fluid and only lost about an ounce in the process.
Let me know if you have any questions.
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