hey guys! so my 03 hummer h2 has a rear main/oil pan leak. i noticed it had it in like september and it was slow leak but that also could be because the temps in alberta were colder. i was running 5w30 synthetic like always. the dealership i got my oil change noticed it and said they cant tell if its the rear main or if its the oil pan, thye would have to do a die test and they quoted laber at minimum $1200.
i decided to leave it alone since at first it was barely leaking. like over 6000km oci, my oil level would go from full to half way in the dip stick. our winter here was super cold so i didnt notice anything unusual for oil level in the winter.
but now its spring/summer and i noticed that i lost about a quart of oil over the past 3 months i would say which is way more then what i was losing in the past. i also noticed the puddle under my vehicle is larger then it was before. i tbh will only be driving this vehicle for the next 6 months and then it will either be parked or rarely driven so i dont really want to spend all that money on the labor to fix it.
i was also thinking of running a hm oil. so right now, since the temperatures are always 20 celcius and above this summer and it wont be getting cold for another like 4 months atleast, i was thinking of maybe running a 10w40 hm or something? or should i NOT do that since ive always run 5w30 in the past? because if i do drive this in the winter i will have to go back down to a 0w30 or a 5w30 because it is regulary -30 celcius here in alberta during the winters.


thanks!

 

Mine was leaking alot also & I finally bit the bullet and changed the rear plate/rear main seal & oil pan gasket. This stopped the leaking. I think you are going to have to eventually change both sooner vs later...

 

thanks for the reply! it seems to be the case for sure but i asked a local mechanic and he said it won't get that bad that i will ever have to actually change it. hes like if i only drive it for a year for example, even if i have to add 6 quarts over the 1 year. thats only $50 of oil a year compared to $1000 of labor.

not sure how true it is, but like could it ever just blow the seal or gasket and start gushing out or is that unlikely?

 

Dont change the viscosity.
Go to wallyworld for the stock up deal($22.38/5qt Advanced or High Mileage full synthetic)!!!!!!!!!!. I don't go to the stores, I make it $35+ to get free delivery!
----->>>>> Mobil 1 High Mileage Full Synthetic Motor Oil 5W-30, 5 Quart

I don't know why the links keep changing? https://www.walmart.com/ip/Mobil-1-A...Quart/17034372

 

thank you!

 

you can try at-205 or blue devil rear main sealer

 

rear main leak caused by debris trapped in seal. oil pan gasket deteriorates/possibly check pan bolts torque? main thing that causes engine oil leaks, is excessive pressure, check pcv/crankcase ventilation system. Also make sure to monitor the fluid level.

 

i cant remember where i heard it but someone said gm rear main seal is made of teflon.
in this case, these seal products dont help

is that true?

 

I had some oil leaks and was told it was unlikely to be the rear main. So I replaced the oil pan gasket and valve cover gaskets and all was cured. It's been leak free for over 7 months, which is the longest stretch in the past 5 years.

 

I had a leaking rear main seal in my '03 H2 and I can confirm ATP AT-205 has stopped the leak completely. I've also used it on my front differential which was leaking as well. It stopped the leak there also. It's expensive, but I can attest, it works for both of these minor leaks on H2's.

https://atpautomotive.com/re-seal