Provent vs HPD Catch cans; a real world comparison

Catch Can Comparison

If you’ve been following along, you’ll know my new Dmax was fitted with a  HPD catch can not long after getting it as a catch can is a sensible idea, and they were the most highly recommended by a huge number of workshops and individuals.

A few months later, I received a report from Curtin University showing how poorly the HPD catch can performed in a laboratory test when compared against other catch cans. Of course, given the study was funded by Mann and Hummel a lot of people said the results were flawed and the testing was done to make the Provent and Flashlube Catch cans (made by the same OEM) look better (as they outperformed everything else).

I very much disagree with this as University’s put a lot on the line to run their testing, they have a lot to lose if any fraud is involved and at the end of the day they have to be funded by someone. If you built and sold a quality product you’d want an independent test done too, which would show the truth without any bias. No one else is going to pay for it to be done!

Isuzu Dmax Catch Can
The HPD catch can I had fitted to my Dmax, and have since replaced.

Despite this, I kept the HPD fitted for many months after that, simply because there was no where suitable to install a Provent 200. That is until Western Filters brought out a new kit which dual mounts the Provent Catch can and the normal secondary (aftermarket) fuel filter on the same bracket.

About a month after it was released, I picked up a dual mounting bracket and Provent 200 for $360, and fitted it. The HPD catch can was sold second hand for $250, and I continued collecting oil to see how the two catch cans performed in a real life situation, to complete a HPD catch can review, and a provent catch can review.

Provent 200 in a Dmax
The new Provent 200 dual mounting setup on our Dmax

I knew running a catch can on modern turbo diesel motor was a smart choice, and was pretty annoyed that I’d blown $385 on an aluminium HPD catch can that didn’t collect nearly the amount of oil you’d want it to.

What made it worse was I chatted to the sales guys at HPD, who assured me it was almost as good as the Provent 200, without some of the downsides that the Provent has. If you want to see the report from Curtin Uni, my initial results and overall thoughts of the HPD Catch Can, check it out here: Why I’m removing my HPD Catch Can.

Installing the Provent 200

If I’m totally honest, installing the dual kit was a real headache, and not something I enjoyed at all. Part of this was because I had a different kit already for the fuel filter, which had to be undone and removed, then turned around and with a larger battery it only just fits.

You’ve got to be pretty careful when playing with fuel lines, and having the catch can and fuel filter mounted off the same bracket means things are very tight. I’ve got giant hands, and that doesn’t mix too well.

Provent 200 install
She’s a tight fit. The Catch can was a piece of cake, but the fuel filter was a pain

I fitted the Provent at 34,773km, and weighed the brand new, dry filter at 86 grams. It takes a while for their filter to wet and actually start oil, but the results below are from when the catch can was brand new to now.

Provent 200 brand new filter
A brand spanking new Provent 200 filter weighing in at 86 grams

HPD vs Provent Catch can real life test

Thus began the Provent vs HPD catch can test, with zero commercial interest involved. I paid my own hard earned money for both catch cans and kits, and can proudly say I have never received a dollar or any products from either business. 

I expected that the Provent 200 would catch a lot more oil than the HPD ever did, not only because of the laboratory testing that was done but just by looking at the two units side by side. The internal design and filtration methods are worlds apart. That said, I was still surprised at the difference in how they performed in a real world environment. I wasn’t expecting such a big gap.

Empty test beaker
The test beakers, weighing in at 27 grams empty

HPD Catch can results

I ran the HPD catch can on my Dmax for 34,000km. It caught 125ml of oil (eye balled; 97 grams of oil), which works out to be 37ml every 10,000km. I then removed it and installed a Provent 200.

HPD Catch can
The inside of a HPD catch can
HPD Catch can oil caught
34,000km of oil collected from the HPD Catch can

Provent Catch can results

I’ve collected every drop of oil from the Provent 200 (like the HPD above) and put it into a container over the 5625km I’ve had it on for. The total catch so far is 138ml (eye balled again; weighed in at 105 grams).

That’s 245ml per 10,000km! Interestingly, the dry filter which was 86 grams now weighs in at 126 grams, so there’s a fair bit of extra oil inside the filter that has been caught but not dropped out into the drain tube just yet.

Ultimately, in just 5625km, the Provent 200 has caught more oil than the HPD did in 34,000km on my 2016 Isuzu Dmax, and that’s not even considering the 40 grams of oil that’s caught in the filter at this very minute. It’s pretty clear what the best catch can is!

EDIT – In about 40,000km I’ve collected some 1200ml of oil, which I have sitting in the garage. It really is quite phenomenal.

Provent 200 filter
The Provent 200 filter after 5625km; doing its job!
Provent Catch Can results
5625 km worth of oil caught in the Provent 200
40 grams of oil in the filter
An extra 40 grams of oil sitting in the filter which has been caught, but ignored in this test

HPD vs Provent Catch cans

The results speak for themselves. In this test, the Provent 200 caught 6.5 times more oil than the HPD. Of course, there are lots of things to look for when buying a catch can, but in my opinion the most important is how well they actually filter, and separate the nasties. It also means that I’ve likely let a heap of oil go through my motor in the duration the HPD catch can was on, which I’m not too pleased about.

Provent vs HPD Catch can
A picture tells a thousand words

It also means that the testing Curtin Uni did was pretty much spot on, in the fact that the HPD catch can is about 6 and a half times less effective at catching the mist and separating the oil going back to your inlet compared to the Provent 200. Their results showed 5 x less effective filtration.

Interestingly, the HPD catch can caught a reasonable amount of water. I can’t be sure, but its possibly condensation from the aluminium heating and cooling, as I get none of that with the Provent 200. What’s even more disappointing is the HPD Catch can actually costs more money than the Provent 200, right out of the box.

Beyond this, the facts are pretty simple. Mann and Hummel are found in more than 80 locations world wide, have over 21,000 employees and in 2018 had sales revenue figures of around 4 billion Euro. They also provide OEM catch cans to a myriad of different industrial and commercial and passenger engines, and up until recently were the only filtration company making catch cans (just recently Ryco have stepped into the game).

Realistically, I feel rather daft falling to sales tactics and listening to the herd mentality that suggested the HPD was better. Anyway, you live and learn, and hopefully this will help others making the same decision about What catch can to buy.

If you are looking to purchase a catch can, and are weighing up whether to fit a HPD or Provent, you’d be mad to go past the quality German engineering that Mann and Hummel have to back their products up. I know which one I’m keeping on the Dmax, and what will be fitted to future vehicles. It most certainly isn’t made of billet aluminium!

Testing errors

Now, I can already hear some of you saying ‘there are too many variables’, ‘your engine oil was different’, ‘the car now has more blowby’ etc etc. You don’t have to believe what I’ve done here, and you are welcome to question any of it, but it was done extremely carefully, honestly and with zero commercial intent.

For some further information, the engine oil viscosity has remained the same, the driving style and vehicle use is very similar and considering the Provent has only been on for 5600km its pretty unlikely my motor has all of a sudden developed bad blowby.

Even if there were some variables and error, do you really think that any of those would result in a 6.5 times worse filtration ability? At the end of the day the difference between these two catch cans is chalk and cheese. As someone recently put up on the 4WDing Australia Facebook page – ‘Let me guess. One looks great and the other works great’.

Downsides of the Provent 200

With anything you buy there’s always an element of compromise. The Provent 200 is a massive unit, and finding somewhere in the engine bay to mount it isn’t always easy. For older vehicles, its not an issue as there is always ample room to play with. Most modern vehicles though, have extremely limited space and finding a suitable spot to mount it and route hoses is a challenge.

Western Filters themselves have released a few kits for the 2012 – 2016 Dmax’s as it is such a problem. Beyond this, the Provent 200 has a filter that needs replacing roughly every 40,000km, and at $80 it does add up over the life of the vehicle. The HPD has no filters to replace, as they are just bits of stainless steel mesh. 

As the Provent 200’s work so well, you have to drain oil regularly. Put one on an old vehicle with lots of blowby and ignore it for 5000km, and you may have a problem, as the catch can will eventually fill up. I can see it filling the drain hose on my Dmax as the kilometres rise, and make sure it is emptied every 1000km or so. I don’t actually know how much they will safely hold, but you don’t want the actual cans filling up with oil.

I sucked oil out of the HPD catch can about 3 times in the 34k it was fitted as I couldn’t undo the bowl easily. I guess if you catch less oil, you have to empty them less!

Isuzu Dmax
Nothing is perfect, but I’m much happier with the Provent 200

What do you think, and what do you run?

What catch can do you run? Do you like it? If you run a HPD, please don’t take this personally. It’s a real shame that such a popular, and realistically good quality product asides from its filtration ability lacks the performance required to actually be useful. If it performed nearly as well as the Provent, I’d still have it fitted. They do catch oil, but not nearly as much as they should. 

Are you happy with your catch can?

A quick word on dumping to the chassis

I can guarantee that as this gets spread around there will be plenty of people saying just run the hose to the chassis, and blank the inlet off. This is one way to guarantee no oil and muck gets into your intake. It’s also completely illegal, and downright irresponsible. Eventually oil makes its way out of your chassis, onto your driveway, or the roads. 

You literally endanger peoples lives by doing this, as oil on the road makes it easy for motorbikes in particular to slip over, or normal vehicles to have uncontrolled handling. Do the right thing by other peoples safety and the environment, and don’t dump it into your chassis.

Further updates to come

I’ll keep updating this with how much the Provent 200 catches over the next few months and years. Again, this is my results, my opinion and you can take them however you want to. If its been of value, please do me a favour and share it around, so future catch can buyers can make an educated decision and do their own research!

Se you out there

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  1. Hey Gary,

    Yep, they are the pick of the bunch if you are going to get a catch can. How often are you replacing the filters, and are they genuine ones?

    Take care

  2. Gary clarke says:

    4 years ago I fitted a Provent 200 catch can after doing some research and I’m 100% happy with it I have a 2008 mazda bt50 which hhas 260000klms on it and co believed I made the right choice.

  3. Hi Glenn,

    They are not two conflicting test results. One was taken at 27,000km, and the next at 34,000km. Given this was nearly 5 years ago, I don’t recall the exact details, but more than likely we did more towing during the last part of the test, or the HPD catch can requires a bit of oil to sit in the mesh for it to start working better. If you read the post it was eye balled as well, on a 250ml jug, which might not have been perfectly accurate. If you want absolute figures, it was 97 grams over 34,000km.

    It has been well proven by Curtin university, plus myself, and a HUGE number of others who have gone from a HPD to a Provent that one does a really good job of filtering, and the other does a very mediocre job. I paid my own money for both units, and couldn’t care less which one does the better job, but wanted to share my findings as I was quite annoyed by being misled.

    As I mentioned in my other reply, the amount of oil you catch is completely unrelated to what someone else catches. It depends on the engine, age, wear, ambient temperature, load (towing/not towing), oil grade used and a myriad of other factors.

    I did have a tiny weep from the initial HPD catch can installation, as the hose clamps it comes with are not good enough at sealing, but don’t expect it would have lost that much.

    I regularly see 250ml of oil in Provent every 10k, and that’s excluding the oil caught in the filter which has not fallen down. The facts are there; you can choose to ignore them because you believe the HPD catch can is as good, or you can open your mind and do some more research, and speak to those who have run both, and you’ll find some interesting results.

    If you fit a Provent 200, I guarantee you’ll see FAR more oil caught than you currently do.

    All the best

  4. Glenn Sheppard says:

    Curious as to why you have 2 conflicting test results. in this post you claim you tested the HPD can over 27,000ks and averaged 24ml per 10,000ks, however on another post you claimed you did the test over 34,000ks and averaged 37ml per 10,000ks. Either way it is conflicting and not very accurate. I am using the HPD can on a 2017 Pajero Sport and regularly get around 105-110ml every 7,500ks. You claim you only drained 125ml over 34,000ks, which is totally unrealistic. Seems to me to be a very biased or incorrect test or you had a problem with your HPD can.

  5. Hey John,

    My Dad has a similar era and KM Pajero, and I recall reading that they have issues with sludge build up that is often far worse than other motors. A thorough mechanical clean and a catch can will help a lot

    All the best

  6. John Sipolis says:

    Hi, i have a 2020 Pajero 3.2 with 55.000kms on it. I just had the egr removed and cleaned be cause it was full of carbon buildup, it was running rough and intermittent power loss with the warning light on the dash. I was surprised this happening at this early stage as i do some highway driving and using Fuel Doctor if that helps, not sure. Anyway i had it fixed not by Mitsubishi and it’s running great now. I had a Provent 200 fitted so i’m keen to see how that works and hopefully no more similar problems.

  7. Ross Mills says:

    G’day Aaron, we have a 2015 hilux 3 litre base for a small 4×4 motorhomes. It has done approx 72000km, rarely used on short round the town trips. Our mechanic suggested at our last service we fit a catch can. After reading some of your excellent articles and various comments I can’t see any reference to a hilux. Have you any advice for an elderly, non mechanical couple? Thanks, Ross