[Repair Log] M45 Oil Pan Replacement

[Chunjee]

Attempting to replace the oil pan on my wife's 2006 Infiniti M45. I was an idiot and put a giant hole in it for her (pics below)


I saw this described as "the worst oil pans on the planet to change" so I'm not expecting it to be a walk in the park. Shop estimate to do it is $2200 and I'm hoping it doesn't come to that.

I'm posting as I expect to have questions and because I didn't see much in the way of advice on this repair online.


For the record. I attempted to patch this up with fiberglass and RTV. If you are reading this sometime in the future and attempting the same, I would highly advise patching with RTV/JB Weld THEN fiberglass as it's just hard to get a good hold on aluminium with fiberglass epoxy.

The damage:


Prep for fiberglass:


Not holding oil by itself:



RTV does a better job:


The summer heat has taken it's toll on this repair. Aluminum will expand and contract under hot and cold conditions, and this is no longer holding well.

[Ilya]

Oof! That'll leave a mark. What did you hit?

[Chunjee]

I was an idiot and went too fast over a speedbump. Came down hard on a large lane dividing bump. Why am I in the center of the road anyways? I was preparing for a turn after the bump.

Under this vehicle is a steel plate that protects the aluminium oil pan well from possible rock damage, but I narrowly missed it thanks to the speed and angle of the bumps in question. I'd say this problem rare but In my quest to find someone solving this on youtube I did come across some similar damage:



According to translation, that guy's customer hit a manhole cover opposite of the side I took inpact on.

[Ilya]

I once hit a manhole cover myself but luckily my Tollbooth Willey engine guard/tray said, "no thanks manhole cover, we don't want to meet" and protected my engine.

[Larz]

A new oil pan and gasket from Infinity parts online is slightly over $250.
I just googled. The engine must be lifted out and supported with a brace and chains. Only the M45's require this. The M35 is simple remove and replace.
The dealer price for the parts is usually close to double what you and I pay direct from Infiniti, so they will charge you $400-500 for the pan and gasket. Then they add another $1500 for labor which sounds about right. I reckon it is an 8-hour job for them.
Sorry to see you stuck like that. After over $2,000 for a new dash, I feel your pain.

An idea: If you have comprehensive insurance, this is considered damage by road hazzard and it will likely be covered by insurance, less your deductible.

[EdBwoy]

I'm just passing by to offer encouragement and wish you luck. Unfortunately, if you throw the right combination of factors, the design of the 06-10 M45 bottom will have you scrape the oil pan.

It has happened to one of our cars:
09-m45-oil-pan-crack-t617765.html?hilit=Oil%20pan

[Chunjee]

I'm just passing by to offer encouragement and wish you luck. Unfortunately, if you throw the right combination of factors, the design of the 06-10 M45 bottom will have you scrape the oil pan.

It has happened to one of our cars:
09-m45-oil-pan-crack-t617765.html?hilit=Oil%20pan

Wow I wish I had come across post prior to my first attempt. JB Weld seems to grab the aluminium well.

[Chunjee]

I got tired of worrying about the wife's oil spilling out. I tore the entire "repair" off and got it as dry as possible and hit it with a wire-wheel again. I used a quick drying JBweld epoxy to fill in the thin cracks then covered the entire thing and thumb-sized hole with JBweld SteelStik to act as a reinforcement and cover so the thinner epoxy could cure. Now Steelstik cures in under 5 mins so as it was hardening I pressed along the edges a lot to hopefully create a good seal there as well.

Waited about an hour and started getting phonecalls from the wife that she wanted her car back. Filled it with oil and returned it to her.

The repair is much improved. I haven't seen any leaking, and I checked the oil level this week, looks great.


I think an even better fix would be to use regular JBweld + SteelStik and let it cure over 2-3 days.


Will post some pictures when I get a chance.

[Chunjee]

This repair is holding. This week I added some more epoxy along where the putty meets the aluminium mostly as a precaution:

[EdBwoy]

This is good to see.

The repair I did also held up well for over 2 years...until the car got wrecked.
My video got a good number of "Just pull the damn pan!" Comments, but sometimes a repair works just as well as a replacement. Sometimes.

[Chunjee]

That underbelly which would be highly recommended to better protect this area: https://www.tbwperformance.com/2006-201 ... ray-black/ / https://www.tbwperformance.com/m35-m45/
SKU: M35M45EngineBK
$199 at the time of this posting

My wife decided to sell this M45 which was primarily hers. We love this car and the repair seems to be doing fine; but we had another child and this is starting to not fit. The new owner is aware of this less than ideal repair.
I love the power of this engine but its a little pricier to maintain and fuel. My favorite car we've ever had.