Massive Oil leak, broken oil filter housing base. Wear and tear or shop error?

I’m going to say it likely is not shop error. Oil filters are not torqued on very tightly at all (tightened by hand only), so it’s hard to imagine how a shop could cause that damage. But I’m no pro, and can’t claim to have seen it all, perhaps others could chime in.

 

I would find it very unlikely that damage could be caused by removing or installing an oil filter. The oil filter torque spec is 13 ft-lbs. It would take an impressive amount of twisting force to crack like that and castings don't just break. I don't see any obvious mechanical damage in that area, so I doubt it happened from road debris or anything similar. What I could imagine, is if some other work was done in that area and that person was using a prybar (or similar item) to wiggle something around and was prying against that housing or something. Any other work been done to the car?

I'm also thinking that 'base' is actually the upper half of the oil pan. The lower oil pan is a stamped steel cover that has the drain fitting. The upper oil pan is an aluminum casting that bolts to the engine block. It looks to me like the "oil filter base" is part of that aluminum casting. If so, it's going to require replacement of the entire upper oil pan. The area where that crack is located has two rubber o-rings that seal the flow passage between the oil filter and the engine block casting. That crack either goes through the oring area resulting in a leak, or the crack is preventing the fastener from sealing the oring.

Replacing the upper pan is NOT a small job, but they are available on ebay for $100-200.

 

I really find that hard to believe. The amount of force required to crack the housing would crush the filter before it cracked a cast metal housing. I could be wrong, but that's my impression.

 

Sorry to see that failure.
That sucks!

 

Not enough information

 

The first 5 seem to be about cars other than a Gen 2 Prius. Nothing they said would sway me from my opinion as the housing is cast aluminum, not plastic like one of those mentioned.

Just trying to be pragmatic, but ultimately the call is yours. Do what you think is best.

 

Another reason I get my oil changed at my Toyota dealer.

 

On third gen there's a bolt-on aluminum piece that the oil filter screws into. On second gen, does the oil filter screw directly onto the "upper oil pan" casting? Seems to be.

Some info from Amayama:

Main page:

Cylinder block for Toyota Prius XW20, 2 generation, restyling 11.2005 - 05.2009 - Toyota Car and Auto Spare Parts - Genuine Online Car Parts Catalogue - Amayama

Detail:

Buy Genuine Toyota 1211121060 (12111-21060) Pan Sub-Assy, Oil for Toyota Prius. Prices, fast shipping, photos, weight - Amayama

Toyota USA's main part site (linking to McGeorge Toyota), has it (upper oil pan, the aluminum casting), new if I'm not mistaken, for $117.35 USD:

https://toyotaparts.mcgeorgetoyota.com/oem-parts/toyota-oil-pan-1211121060

 

If it was something the oil change shop did, then it would have leaked immediately and you would have seen oil on the ground under the car where it is normally parked. It seems strange that you drove it for a month then all of a sudden you lose two quarts of oil and likely seized the engine. I still do not believe on a Prius you can crack the housing by overtightening the filter, it is pretty sturdy. I've never heard of this happening before in the last ten or so years.

Unless you can find examples of others with a similar design as used on the Prius, so other model Toyotas for example, I don't think the examples you have dug up will carry much weight.

I would never say never, but figuring out what happened and then proving it will be an uphill battle.

If it were me, I'd also be having a certified professional come out to the car and inspect it and write up a report on what s/he thinks happened here.

You haven't mentioned whether you're insured, but if you are not then that double sucks, because you could do with that option to go into bat for you.

Not trying to be obstructive, just trying to give you an idea of what you'll be up against.

As has been said it sucks that this has happened to you and I wish you all the best for success.

 

As Dolj says above, if damage was done at the oil change shop, you almost certainly would've noticed puddles of oil under your car within a few days. In addition, you seem to imply that your oil light was on right after the oil change. Why wouldn't you get that immediately addressed with the shop? I can't imagine taking my car for an oil change, leaving with the oil light on, and ignoring that. All that said, I've stopped having a shop (Toyota dealer too) do my oil changes due to numerous screwups. I now do my own oil changes.

 

Ok, so some engine designs use a filter cartridge that goes into a plastic housing (such as Chrysler 3.6L). Overtightening the filter cap can easily break something and cause leakage.

Some designs have a spin on filter that attaches to something that's "not so sturdy" that can have problems (such as the oil cooler "filter base" on Nissan 3.0 or 3.5L or many Ford V8s) it can twist and leak.

If there's any problems with a spin on filter, it won't be on installation. You can't really tighten it enough to cause immediate damage- that would make the filter leak. Things go wrong when you try to remove the filter.

If the filter is over torqued and/or installed dry (no oil on the rubber seal), then the filter can feel like it's welded in place. Now you need large tools and lots of force to loosen the filter. Sometimes I've had to destroy the filter in order to get it off.

Other than a couple of times when a cooler had to be repaired (Nissan or Ford), I have never seen damage to the filter mount.

Can't tell decisively from your pic, but it almost looks like something struck that area of the casting. I don't see how the shop could have done this as it would not have gone for a month and then started leaking. If it was leaking all that time (your low oil pressure warning coming on? it's NOT the "oil level low" warning) there should have been oil all over the ground all the time.

I have difficulty imagining that you ran over something and it flew up and hit the engine. I'm not sure I could crack that if I tried.

The filter base is part of the upper oil pan casting, which would have to be replaced. You also don't know if the engine was damaged by loss of oil pressure.

Posted via the PriusChat mobile app.

 

"Tow guy asked me..."

Unsubscribed....

 

? Tow guy pointing out to the lady why she may be losing oil?

For the lady's perusal, not for ASE mechanics. Couple of photos show the cracked tab on the upper oil pan, oil pump passages into and out of filter. Highly unlikely from tightening the filter. Coincidence that the upper ear tab cracked at the same point in time?

Not sure if you have the funds to repair, the upper oil pan part may be $50 from auto salvage near you. Install?? Rest of engine block condition? Complete engine probably under $500 from salvage. Again install cost?

Look for oil pan engine part, upper, not lower.
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