Use caution there, oil collects in little holes in the bellhousing etc and will continue to seep after the leak has stopped. I had a car that kept dripping after an oil leak repair and had to end up drilling holes in a couple places to release trapped oil.

So shoot your dipstick with your dye check light and glasses, if the oil is glowing, but the oil you see dripping is not, then it may be residual oil.

On the oil pan gaskets, they all leak, it's not if they will leak it's when. On 4wd's I've always pulled the front axle, it's actually pretty easy and the unit is not that heavy.

 

Thanks, ill probably try to drop the axel this weekend and pull the pan. Good time to get a junkyard axel and swap it in, since my axel makes annoying groan noises from about 15-30 mph when the pinion gear is unloaded during coasting. I think this is a symptom of the pinion being set up wrong, although its gone many miles like this I just hate the noise, shouldn't be hard to swap in another one from a junkyard and they shouldn't be that much money either. I think trying to rebuild mine would be a pita and I don't think I have the tools for it.

As for the dipstick, the oil on the dipstick looks basically exactly the same as the oil dripping and collecting on the bellhousing and oil cooler, but it definitely is harder to see the oil on the bellhousing and oil cooler than what's on the dipstick. There is also a lot of other stuff that shines that yellow glow under the blacklight and glasses, but its just dirt or mud or whatever else is up under there, so it makes it even more difficult to spot anything. Given that the dipstick oil and the collected drops of oil on the bellhousing and oil cooler are the same color, I would think that means there is a continuous leak that is still present.

 

to drop the diff you need to drop the steering from the idler and pitman arms. Those can be a pain in the rear.

Once the steering is dropped, you can drop the diff and remove the pan. If you're pulling it out to replace the gasket I have some tips:

AA) degrease and pressure wash the underside of the engine before turning any bolts
1) clean the pan inside and out, there will be residue in the pan; dirt and shellac/sludge and debris
2) clean the bajeezus of the outside of the pan
3) you'll need some 1/8 rivets and a 3/16"+ drill to drill the heads off the old ones
4) you'll need a rivet gun
5) RTV the corners of the pan for the front/rear cover interfaces
6) helicoil the oil cooler holes. You'll regret this if you dont
7) quality gaskets, nothing made in chinesium. ACD, Victor Reinz, Fel-Pro, Mahle

When you reinstall the pan, pay attention to the order of assembly and use the trans bolts and the pan bolts to make sure the trans seats all the way to the motor and to the trans. Dont just rattle the bolts in there and hope for the best. Finesse them in, little by little tuning each bolt to ensure that the pan is mated to both surfaces

I did this ~2yrs ago when my oil cooler was leaking, Start to finish took like 3hrs, its not very hard. Lots of bolts, but everything is easy to get to. My saving grace is my truck was a lot cleaner underneath, so I could see everything that needed to be removed pretty easily

 

Thanks, I didn't know the oil pan gasket was riveted on! At this point, I think I might just pull the whole motor, put in a higher stall torque converter, put the set of 706 heads I have on there and put a cam in it haha, im kind of serious, especially since I have to do all this without a lift.

 

Thats an option too!

Yeah the gasket is held on with a rivet on each side, 2 total

 

God I forgot that generation uses drag link steering on 4wd trucks. I've gotten lucky and only had to put front diffs on trucks with steering racks.


On the oil pan fitment I have a few tricks. To each their own on re installing rivets in the oil pan gasket, I never have ever. Just drill the old rivets and rip the gasket off, will usually pull part of the rivet out with it.

On the pan alignment. I have a method I came up with that I like.

After all the cleaning is done the gasket is sitting on the pan with a few bolts threaded into the holes on the gasket to hold them in place, and your 4 dots of silicone are applied...
Set your pan up to the block and thread in a few bolts to hold it.
Go ahead and thread all of them in at this point, but leave them all loose. NONE snugged up just yet.
Now push up on the pan or very very lightly snug up a couple perimeter bolts near the rear, the point here is to allow the pan to slide forward reward the tiny little bit it can on the bolts so it cannot be tight at all. Just have the pan up making light contact with the block.
Now snug down the 2 bolts that go through the bellhousing into the lower oil pan, you're doing this to pull the pan all the way back to the transmission.
DO NOT TIGHTEN ANY BOLTS ON THE REAR OF THE PAN THAT GO UP INTO THE ENGINE AT THIS POINT if you tighten a rear bolt that goes upward into the block it will crack the pan.
Now that the pan is pulled all the way snugly against the transmission you can tighten 2 of the very foremost front oil pan bolts. This will make the pan retain the pulled back position, but won't put pressure on the pan and crack it.
Now loosen the 2 bolts that go through the trans to the pan, and tighten all the perimeter bolts to pull the pan upward. If you try to tighten the perimeter bolts with the trans bolts tight it will crack the pan.

Now your pan is pulled all the way back, and all the way up, and you can tighten the final 2 bolts that go through the trans

 

https://www.performancetrucks.net/fo...an-4x4-554341/

 

Thanks everyone for all the help I appreciate it.

So I would imagine no one else cares about the rivets, I wonder why they need the rivets? I also wonder if the factory service manual says you are supposed to use a combination of the gasket and silicone like I see people do as well?

What's funny is that the GEN V LT1 stuff they changed from using gaskets to RTV on the oil pan and covers, which everyone complains bad about haha. I did a cam in a GEN V and I guess it wasn't too bad to RTV and reinstall the front cover but then again when you are cramped up in there holding the pan with one hand while there is RTV all on it and your having to be extremely careful not to let it touch anything and mess up the RTV bead and make a mess and on the other hand you are using your other hand with the RTV tube or gun (I'm not sure how much the RTV gun thing I had worked) and your trying with one hand to keep making the bead. All while you've got barely any room and you've got wiring dangling from the cover your trying not to break as well and trying not to pinch too.

It seems like they may have went to RTV on all the covers and pans for this reason? Maybe they can't engineer it to reliably seal over time with metal and plastic gaskets? I've always wondered about why all the inconsistency, the oil pan has a weird metal/rubber combination gasket with rivets, this other cover has a random paper style gasket, this over here has RTV? Doesn't make sense unless there are hidden engineering/cost reasons for it.

I am kind of looking for an excuse to have to pull the motor so I can put in a higher stall torque converter, cam and heads. I just hate the fact of having the truck down when I need it most right now because of the rain and snow. I really don't want it down waiting a month for them to grind me a new cam or waiting on backordered parts. I usually hate that so much I end up putting it back together and taking it apart again.

 

you need the gasket on the gen3, its about .110" thick and without it, holes wont line up. Most of the gaskets on the gen3/4 are rubber bonded metal, and that gasket thickness is accounted for in the design. I can't think of anything on the 3/4 that is paper or RTV instead of o-ring or bonded

I care about the rivets and I use them. C5, Tahoe, engines on the stand: all get rivets. I have the tools, it makes my life easier and the factory thought it was important. With the way GM likes to pinch pennies, and the 3 million LS motors they built... they could have saved a good amount of money not riveting if it didnt add benefit

 

GM (or any other factory) does lots of things for reasons that have nothing whatsoever to do with the success or failure of the end product. They are strictly "manufacturability" things. Things that make the manufacturing process easier, faster, more reliable, or otherwise cheaper.

Those rivets are almost certainly such a thing: they're just there so that in handling, before assembly, the gasket stays put. Once assembled they serve no function at all. None.

Those little push-on clips they put on brake drums, or those annoying screws that hold rotors to hubs, are the same way. Useless as **** on a chicken (or worse) once the full assembly is complete; but avoids pieces falling off during shipping and handling while undergoing the process.

Speaking strictly as a sometimes manufacturing engineer...