Rear main Seal

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Rocket Man

Mark
Supporting Member
Joined
Dec 25, 2014
Posts
25,961
Reaction score
50,621
Location
Oregon
This morning I removed the starter to inspect the crankshaft position sensor. There was oil on the block where the 2 starter bolts go but the sensor wasnt wet. I went ahead and replaced it and added some rtv on the o-ring.

Sort of leaning toward my issue being the rear seal. Since the transfer case has to be removed it doesn't look so hard.

Is there a gasket between the transfer case and the transmission??

Im just trying to see what all parts I need before I dig into it. I already have the dorman rear seal with gasket laying round.
I would not install a Dorman part in any location that isn't easily accessible because they are cheap and will fail quickly in most instances. Definitely would not use their rear main seal- you are basically doing $1000 worth of labor to replace an inexpensive part. Use the best part possible. I went with OEM on mine.
 

Rocket Man

Mark
Supporting Member
Joined
Dec 25, 2014
Posts
25,961
Reaction score
50,621
Location
Oregon
@lspann3525
I used the Dorman RMS kit 4+ yrs ago and 56k miles ago. No regrets. Mine is still dry as a bone.
I don't remember changing a seal between the tranny and tranfer case.
https://www.tahoeyukonforum.com/threads/rear-main-seal-job-pan-etc-07-yukon-denali-6-2.108334/
I’m glad it worked out for you. My experience with Dorman has been hit or miss and considering how hard it is to replace a rear main, I won’t be taking a chance myself. My OEM was in for 150k and still not leaking when I replaced it with the same as preventive maintenance.
 
OP
OP
L

lspann3525

Member
Joined
Feb 22, 2023
Posts
76
Reaction score
98
The Dorman kit I have comes with a new cover,bolts,seal and gasket. It's suppose to be an improved designed. All the other brands came with just the seal.
 

Rocket Man

Mark
Supporting Member
Joined
Dec 25, 2014
Posts
25,961
Reaction score
50,621
Location
Oregon
The Dorman kit I have comes with a new cover,bolts,seal and gasket. It's suppose to be an improved designed. All the other brands came with just the seal.
AC Delco and other brands sell the same setup with the seal already installed in the cover. That’s all I’ve ever used. If you trust Dorman, then you trust Dorman. I don’t. They’re the cheapest aftermarket brand there is, and they have a high failure rate. Ask anybody on this forum. I’m sure as hell not using their stuff on something as hard to get to as a rear main seal. OEM lasts 150k or more.
 

Geotrash

Dave
Supporting Member
Joined
Feb 16, 2018
Posts
5,482
Reaction score
12,961
Location
Richmond, VA
AC Delco and other brands sell the same setup with the seal already installed in the cover. That’s all I’ve ever used. If you trust Dorman, then you trust Dorman. I don’t. They’re the cheapest aftermarket brand there is, and they have a high failure rate. Ask anybody on this forum. I’m sure as hell not using their stuff on something as hard to get to as a rear main seal. OEM lasts 150k or more.
I find them to be hit and miss but generally trending better. I've used a Dorman throttle body and a Dorman suspension compressor on my '07, and both have been working great for 3-4 years so far. And the Dorman bushing for the transmission shift linkage is superior to OEM, in my opinion. That said, if I can get ahold of the OEM part, I generally do unless the Dorman part incorporates a meaningful improvement, as was the case with the throttle body.
 

Rocket Man

Mark
Supporting Member
Joined
Dec 25, 2014
Posts
25,961
Reaction score
50,621
Location
Oregon
I find them to be hit and miss but generally trending better. I've used a Dorman throttle body and a Dorman suspension compressor on my '07, and both have been working great for 3-4 years so far. And the Dorman bushing for the transmission shift linkage is superior to OEM, in my opinion. That said, if I can get ahold of the OEM part, I generally do unless the Dorman part incorporates a meaningful improvement, as was the case with the throttle body.
Dorman is probably getting better, who knows. But I’ll stick with my criteria- if it’s easy to get to in case it fails, or if it’s a better design and is easy to access also, I’ll consider it. But if it’s in a place that requires a lot of labor to access it, never Dorman for me. I’ve been burned before on their stuff. They do have a couple good designs, I’ll admit it and I will use them for that.The rear brake dust shield/ backing plates are one. The OEM design requires the axles to be removed, Dorman designed 2-piece ones that can be installed with the axle in place. The overall quality is typical Dorman though- about half as thick as OEM but if they rust out again, they’re easy to replace. They fit my criteria for easy to access. They also make a oil pan for the 4l60 trans that has a functioning drain plug where the OEM pans don’t. I use that, it makes it easier to drain the trans. It lined up good and didn’t leak. I still don’t trust them for a lot of stuff though, like seals etc or anywhere close tolerances are necessary.
 

JonnyTahoe

Full Access Member
Joined
Apr 14, 2011
Posts
1,249
Reaction score
771
Location
Minneapolis
Crankshaft position sensor is behind the starter. After replacing, a crank variation relearn is recommended.
Replaced my crankshaft position sensor when I replaced my starter. Replaced it with a oem AC Delco sensor. Delco P/N; 213-354 GM P/N; 12560228. After replacing it Engine would not start tried several times. Removed my brand new starter and pulled the brand new Delco Sensor out of the engine. Re-installed the Original Sensor and the engine started right up nothing was wrong with the original sensor I only replaced it because it was 20 years old. Original sensor did not leak a drop of oil. I was lucky enough to be able to re-install it as I almost damaged it trying to remove it. No re-learn required it started right up like it was never removed and years later still running perfectly.
 

Forum statistics

Threads
128,781
Posts
1,805,301
Members
91,760
Latest member
MyCleftNut

Latest posts

Top