[MasoElCaveman]

My car is about to hit 180k miles and is due for maintenance, but I'm not sure if the oil pump had gotten done at 120k or not so to be on the safe side I'd really like to replace it.

Problem is the OEM pumps are discontinued everywhere I look, but I noticed an aftermarket oil pump on 3sx.

I really don't want to go aftermarket for my oil pump, but it really doesn't seem like I have a choice.

Anyone here know where I can buy an OEM oil pump and if not I'd really like to hear some success stories on using aftermarket ones!

 

[MasoElCaveman]

You can buy this one:

OEM Oil Pump Update: Sold

Selling a new Oil Pump for NA DOHC cars 93+. Part number is MD190981. $250 plus shipping gets it. Will throw in the OEM Oil Pump gaskets for an additional $15. Thanks

www.3si.org

And change the relief spring to the TT one (the only difference between NA and TT pumps for 93+), I don't have the part number handy but you can check it with ASA.

Appreciate the confirmation on that. I imagine it can't be too involved to change out that relief spring so I hit him up to buy it. So does that mean the NA pumps are still around a plenty?

 

[MasoElCaveman]

Does anybody know real quick what are the intervals recommended by Mitsubishi to have your oil pump changed out?

I thought it was every 120k miles, but not sure on the time interval

 

[MasoElCaveman]

Agreed.... I usually disassemble and check them while doing a 120K, as well as check bearing condition. I end up replacing around half the bearings I inspect, and a fair number of oil pumps, but I never just arbitrarily replace them because of mileage.

What exactly do you look for when determining if an oil pump looks good or not? I certainly don't have the eye for that and just want to keep my daily reliable for as long as possible.

Was strongly considering getting new bearings too just because of my total mileage, but my shop was saying it's unnecessary preventive maintenance because the labor involved in replacing bearings is similar to what would be done in the event of a spun bearing anyways. Honestly, not positive that bit is true as I haven't looked into the whole procedure enough, but I could see where they are coming from...

 

[MasoElCaveman]

Checking for abnormal wear, gouged material, or clearance out of spec. There's inspection procedures in the FSM.

You have to have the pan off to check the oil pump, It doesn't take much time to yank the main girdle and inspect the lower main bearings. If they're showing copper, that's the best indication you need to keep looking, and likely roll new bearings in.

Great information here I appreciate it!

 

[MasoElCaveman]

I'm not sure that's true, and it would be a good idea to confirm one way or the other... The housing on the 1G is the same, but being as the 4 bolt main block on the 2G TT is wider than the 2 bolt block, I don't know if the pump is wider as well?

In any case, the DOHC Montero pump MD302234 is the same housing and relief spring as the TT pump, but does not have the oil sending unit port in the side of it. You can always get that one and drill/tap the port into it...

I've been doing some reading on here and from what I can tell everyone seems to say the housing to fit the 93+ oil pump should be the same on both NA and TT. Only difference is that relief spring on the pump itself. I've yet to read anything to contradict it so I'm going to hunt down a TT relief spring to put onto a new unused NA pump.

Still need to inspect the pump to see if it really does need replaced, but at 180k miles I want to have a fresh pump ready for when the job gets started just in case.

 

[MasoElCaveman]

You can buy this one:

OEM Oil Pump Update: Sold

Selling a new Oil Pump for NA DOHC cars 93+. Part number is MD190981. $250 plus shipping gets it. Will throw in the OEM Oil Pump gaskets for an additional $15. Thanks

www.3si.org

And change the relief spring to the TT one (the only difference between NA and TT pumps for 93+), I don't have the part number handy but you can check it with ASA.

Hey I've been looking around for that TT relief spring part number, but am having trouble finding it. What's ASA so I may check it out?

 

[MasoElCaveman]

The spring is MD174687

Thanks for finding me that number!

I still can't find anything conclusive on if a 93 N/A oil pump will fit onto a 93 TT. I'm starting to lean towards not. I'll update once I finally confirm.

Drilling and porting that Montero pump would be nice, but that's something I wouldn't even know where to begin. Trying to know to how smooth the port should be for oil flow and all that is way beyond me.

If the N/A doesn't line up this seems like a somewhat serious problem for vr4 owners who need an oil pump as it's gonna be tough to want to trust some random aftermarket pump...

 

[MasoElCaveman]

It's just a missing hole in the side of the pump to screw the sending unit into... You would just drill the hole, and tap it to 1/8" BSPT. Not a major operation.

Certainly doesn't sound too terrible when you put it like that. However, I'm having a lot of trouble finding any threads talking about people installing the MD302234 into a tt 3000gt.

Is the MD302234 from the 6g72 or the 6g74 Montero?

 

[MasoElCaveman]

You can visually compare the two at below link. I’ve organized them for easier comparison below the link.

Tech - Oil Pump Comparison - OEM Mitsubishi Oil Pumps | 3SX Performance Home Page

The world's oldest and largest 3000GT and Dodge Stealth Source for Performance, Maintenance, and Service

www.3sx.com

View attachment 299458 View attachment 299459 View attachment 299460

Thanks for the comparison images! I was actually comparing those last night and was gonna post them, but you saved me the work!

I mean looking at those images I can't spot any differences.

I think at this point I'll just have to visually compare the two pumps and see if any of the pathways are actually any deeper or anything.

 

[MasoElCaveman]

I'm just writing here again to confirm the NA oil pump fit perfectly into my TT. I had the mechanic swap out the oil relief spring (part # MD174687) before installing it. Just got back from the shop and all seems well. Bonus the '99 lifters in there make my engine sound so smooth, am very pleased with the new found silence. That combined with the new polyurethane motor mounts really add a pleasant feel and sound. Though, the rear mount is still the stock one because my mechanic was not comfortable removing it due to how rusty everything is.

I do however have a new issue where my turbo makes this air wooshing sound by the drivers side and my engine hesitates when I do this. Only occurs at half throttle and more as the rpms really rise. But this is a new problem for a new thread, or likely old problem old thread lol. Mechanic did a full boost test and all was sound. Gonna look for this rear turbo o-ring that's supposed to be where it meets the intercooler as that's his main suspicion...

Thanks for the discussion!