Oil Pan Bolts......

[CCiatteo]

I'm getting ready to replace the oil pan on my truck and I'm wondering why the need to replace the bolts? Are they compromised from corrosion as well? Are they torque to yield, single use? Or do the new OEM and aftermarket pans have a thicker flange that necessitate an updated bolts? This strikes me as odd and the cost of the bolts from the dealer is enough to question why. I have searched the threads, but can't seem to find a definitive answer on the subject. I do see that at least one aftermarket supplier is selling extended length bolts as well. So before I dig in, I want to be sure I have the all the correct stuff on hand and the truck is my only source of transportation for work.

Thanks

 

[KOG]

I've not heard of problems with oil pan bolts, but anything is possible I suppose. I'll admit to using blue thread locker on the 04.5 I just built and torquing them to factory spec, but I always do that sort of thing.

 

[CCiatteo]

So I finally did the oil pan today. Here's what I learned.

The new pans you will buy (no matter brand or source) have been updated with a steel "rail" that runs the perimeter of the entire oil pan lip to help spread clamping loads. This "rail" is thick, a solid 1/8th inch is my guess, so new bolts are recommended to account for this additional pan thickness. The new bolts at the dealer are $4 a pop and you need 32 of them.....That's ridiculous. So I ordered up a bag of 50 from McMaster-Carr, (M8 1.25 25mm UHL with serrated flange) for $10.39. The have a larger head (13mm versus 10mm OEM bolt) but still clear the sides of the pan and fit just fine. I used an aftermarket pan (forget which one, but it fit great and was identical to the OEM that came off), cummins gasket.

As for tips on doing the job, I simply did as others suggested:
1) Remove the intake tube entirely, air box can stay.

2) Loosen the rubber boot leading from turbo to the intercooler (on passenger side closest to turbo) and on the driver side (closest to the aluminum intake horn) Oddly enough I found these to be 7/16ths nuts.

3) Loosen the lower band clamp (7/16ths nut) on the exhaust so the down pipe is free. I also removed the bracket for the hanger (2 15mm bolts that thread into the backside of the adapter plate/rear block/transmission.

4) Remove the 10mm bolt for dipstick tube (kinda option, but mine started to hang up on the wiring along the cowl).

5) Remove the engine cover (black plastic thing on top of valve cover, 10mm) optional, but I figured easy enough and maybe I'd need the room.

6) Loosen the two longitudinal motor mount bolts (18mm nut), access from the front is good and mine broke loose without any real struggle.

7) Remove the two transmission mount bolts at the cross member (15mm) so the transmission can pivot. Saw this on a youtube video and it made sense to me.

8) Drive these bolts backwards toward rear of truck so that the bolt head will clear the lip of the motor stand. This was the biggest hang up I encountered as I could not get the passenger bolt to budge, without lots of beating on the bolt. No real good way to get a good swing on it. I ven used an air chisel with blunt face to try and drive it back, but in the end brute force and perseverance won the day.

9) Cherry Picker with chain and hook on the front factory lift point and start lifting, slow and check and look and lift some more. At first the whole truck came up, but on the second attempt, the engine "broke" free and up she went. She did rotate towards the driver side, which due to the lift point being off center, was expected. I didn't find a good lift point that was easy to access on the driver side.

10) Place jack and 12-15" 2x4 at front of transmission pan where pan meets the transmission case and lift just that extra little bit (maybe an 1" tops). Once pan is out, this can be removed for better access while cleaning

11) Loosen and remove all 32 oil pan bolts (10mm) and the old plan slid right out.

12) Clean, prep, and reverse to install.

 

[Wayne M.]

Nice job. Good choice on the bolts!

 

[CCiatteo]

Nice job. Good choice on the bolts!

Thanks.
I'll have to post a pic of the old bold side by side with the new one I used, just to show the difference in length. I think the old bolts might work, but wanted to be sure I had good engagement. I also had no bottoming issues (although I think most of the holes are through holes).

 

[seafish]

NICE work and even nicer write-up!!!

 

[Crunch]

How did you get that hole in the pan (second to the last picture, with screwdriver through hole)? It looks like corrosion, but the only holes in pans I've seen are from traumatic impacts.

 

[CCiatteo]

The hole in the pan was from corrosion, I did "open" it up some by poking at it. But the pan had a big blister of rust on that corner and was "sweating" oil. It hadn't actually started to drip yet and puddle, but that wasn't far off. After I scraped the blister and got all the loose rust off, there was a hole in the pan, but the layers of rust were still able to keep things contained. My fear was a good jolt from a pothole or a piece of road debris could have kicked up and knocked it loose. I tried to take a pic of the hole where you could see dayllight through the pan, but I coulldn't get a good shot of it. All of the other blisters on the pan were just that, blisters, which could probably have been scraped and painted, but not this one.

 

[Wayne M.]

Yup. I changed mine after I rubbed a huge rust blister with my nitrile glove, and it started sweating.

 

[CCiatteo]

So here are the bolt pictures as promised.

OEM bolt below. Useable UHL is only about 14-15mm, total UHL is about 20-22mm. 10mm head

Replacement bolt from McMaster-Carr (M8 x 1.25 25MM UHL) fully threaded with serated flange. 13mm head

The newer pans have the load spreading steel "rail" around the lip that is about 1/8th thick, so the longer bolt is probably not an absolute, but rather good insurance so that you don't pull a thread as you try to attain good torque.

 

[Crunch]

The hole in the pan was from corrosion, I did "open" it up some by poking at it. But the pan had a big blister of rust on that corner and was "sweating" oil. It hadn't actually started to drip yet and puddle, but that wasn't far off.

Wow! That boggles my mind. I've never seen a pan rust through. I guess that's the joy of living in Texas. We don't have a lot of snow, so there isn't much salt used on the roads. Just some "brine" they put on the roads a day or two before the snow and ice hits. But at least we have the 110* heat to look forward to...

 

[TRAMPLINEMAN]

How did you get that hole in the pan (second to the last picture, with screwdriver through hole)? It looks like corrosion, but the only holes in pans I've seen are from traumatic impacts.

My ‘06 was similar to this. Went out one morning and saw a puddle under the truck. Crawled underneath and saw oil dripping from the pan. Pushed on the pan with my fingers and my finger went right thru one corner. All the oil poured out. What was really strange is there was no rust on the outside of the pan as if it rusted from the inside out. I know it didn’t, but it seemed like it.
Yup, the privileges of the rust belt.

 

[Lynx0849]

Wow! That boggles my mind. I've never seen a pan rust through. I guess that's the joy of living in Texas. We don't have a lot of snow, so there isn't much salt used on the roads. Just some "brine" they put on the roads a day or two before the snow and ice hits. But at least we have the 110* heat to look forward to...

The pan on my ‘05 1500 hemi rusted. Was sweating oil. Diligence by the guys who changed my oil found it.
Expensive part and complicated. Heck, gasket was $110.
165k miles and 12 years in the salty northeast.


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