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Charter Member
SM 2003
Full Member
Jan 26, 2002
Los Angeles, California
I was at my dealer today having my Transmission oil ?system flushed (33,000 mi). I met Master Service Technician Pablo Gonzales. Pablo is the inventor and holds patent to the Transgaurd Filter.

The Transgaurd Filter is a unique device which fits on your Transmission line right at the back of the radiator. This device has a internal circular magnet which collects metal particals as well as a metal filter screen. The filter also has an internal spring which is attached to these components so that if enough crap is collected by the magnet and screen, the backpressure opens the spring and allows the unit to flow as it would without it being installed.

GM was not initially happy with this product because it adds a tremendous amount of protection to the transmission and would reduce the transmission failure rates. They are now doing serious testing.

Pablo told me that at 30,000 mi. intervals the filter should be cleaned or replaced. To clean it, just remove it and blow compressed air into the output flow side to backflow any debris collected. The filter can be reinstalled if it appears clean inside.

The Transgaurd Filter retails I am told for over $60.00. I was approached by Pablo after he found out that I am a member of the Avalanche Club. With his doing, all club members can buy this user installable (Takes 3 minutes) Filter from the distributor for $30.00 plus $ 6.50 shipping.

There are models for all GM vehicles as well as Fords.

To get one, call Dan at Airsept and tell him you are from the Chevy Avalanche Club. Give him the year and model of your AV, or additional GM vehicle and he said he will ship out the filter the same day.

I am not involved in marketing this or as always not getting anything financially from it. I did get the unit for free as I promised to pass this along to the club.

Call Dan at Airsept (800) 999-1051



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Here is the filter installed in my truck (See attached photo)


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i'm guessin that this pablo guy installed if for you for free also?
what are peoples take on this?
$60 or even $30 seems like an awful lot of $ for a line fitting with a screen and magnet in it. There is already a magnet installed in the transmission pan and I doubt that the magnet in this device would be strong enough to hold many shavings against the flow of transmission fluid. I am sorry, but this sounds alot like "snake oil" to me. I think I will stick with flushing my transmission every 24 to 30K and leave this device for others to try.
Anybody who's been a club member here long enough knows that I don't yank chains nor screw with Snake Oil products.

I am not going to defend any criticisim on the product because I am not knowledgeable enough with it.

I would like to hear what 11H, Gxx and some of the other knowledgeable engine folks think about it.
Sorry if I caused offense with my reply. I tried to be careful with the wording to avoid doing so. That is the problem with the internet, all that we have to communicate is words, where in person-to-person interaction about 90% of communication is through gesture, tone, and expression. Unlike some other devices, I don't see where this could possibly cause any damage, unless it clogged and the by-pass mechanism failed, in which case the fluid flow would be restricted. I just question the benefit, as the transmission is already equipped with a filter and a magnet. I also feel that the suggested price is very exhorbitant. The cost of manufacture can't be more than a few dollars, however I suppose it has not yet been manufactured in enough quantity yet that the "economy of scale" has kicked in. I still believe you are doing much more to protect your transmission and prolong its life by flushing it regularly than by installing additional filtration. It was explained to me that the torque converter acts as a giant centrifuge during operation and dirt, metal particles, etc. are slung to the case and build up over time. Only by flushing are these impurities removed. Let on their own these impurities will build up to the point where chunks break off and travel through the transmission, blocking passages and generally raising havoc. Regular flushing will minimize this build up.
The first thing I also thought of was the magnets I've seen in the pans of the last two 4L60-E's I've dropped.

I haven't dropped the Av's yet (soon enough), so I'm not sure if it's got one or not. ?As it sits right now, it's got a pan drain bolt, which the others didn't, so I'm not sure what's inside.

XRover - did they give you any intervals to check to see what the screen and magnet are up to? ?(EDIT: sorry - re-read: ?Every 30K. I thought this was for the pan/filter for some reason)

What I'd say differentiates this from the pan-magnet, is that this is right in the fluid's path. ?All of the fluid at some point is forced to cross this thing's path. ?The pan-magnet is bathed in fluid, but it's fairly random as to how it ends up picking up metallic particles.

My personal opinion: ?It's cool. I can't call it snake oil - but I'm still a touch skeptical.
I've been letting this sink in for a while...

Although I still think it's a bit pricey, I'll probably get one and toss it in when I do an external tranny-cooler.
I'm with ya 95% Lenny, but when I see stuff like this I get a little suspicious:

"GM was not initially happy with this product because it adds a tremendous amount of protection to the transmission and would reduce the transmission failure rates."

That's standard "tornado fuel saver"-type marketing BS to be sure, not that I hold it against you for repeating it, but I think we can all agree that GM (nor Ford nor Chrysler) has some sort of plan to make money fixing transmissions so that they would be unhappy with a product that prolongs the life of same. Quite the contrary, I think that reducing tranny failure rates would only make them look better and enhance customer satisfaction.

I am still interested, of course. would love to hear what you see when you pull it out and examine the screen. And your rep for non-BS product feedback is still very intact (y)
I probably won't pull it out for another 10,000 mi or so just to see what it has collected. One thing about it that I didn't mention is that it is a brass fitting and is designed pretty darn heavy duty. It is not a plastic or aluminum fitting.

Is there a scematic or blown up pic of what it consists of ?

Maybe a brochure?

At the least, I'm sure if in fact he was awarded a Patent, that he has some oblique drawings or prints available ...

I would like to see what it's made of before I comment ... So far, all I can see is the exterior of a brass fitting ... I need more Xrover ... Sorry bud ...


Ok, I saw it ...

Here's my opinion:

Looks like it may do what it says it will do, but to what extent is anyone's guess ... Filters / screens work well with a lot of surface area ... The fact that it is so small makes me wonder it's effectiveness... Maybe they have had some worries about warranty concerns and made it look inconspicuous? I don't know ... I DO know I wouldn't spend $60 or even $30 on it ...

My inlook on the gadget is highly skeptical ... Just because of the size of the assembly ... Now here's something I want to know... Is it possible for this gadget to get clogged to the point where the by-pass valve doesn't operate properly? ... I mean hey, if a jagged chunk of metal from the cooler or tranny got in there?

If there is at all any possibility for this to happen, I would steer clear of it ... And if the manufacturer doesn't have a Liability Insurance Policy protecting them in the case of a customer failure, I would REALLY steer clear ...

Xrover, I am not trying to crash the party, but that is an inline VALVE of sorts... If it fails to allow flow, you're up the creek bud... It looks like there are four 90 degree turns the fluid has to take if the screen plugs... Plus, it has to flow passed spring wire ... Scary to me if that screen plugs ... I deal with passive valves at work extensively ... They all have their merits and drawbacks depending on application ... And unfortunately if they are in service long enough, they fail ... As with all valves eventually ...

If I were going to do this, I would like to see a much larger apparatus to work with ... Which I don't know why it isn't bigger ...

It may work as designed in 99% of all instances, but hell, I would hate to be that 1% where it didn't ...

Where's our resident tranny expert Mike56BA ??? ... I bet he's seen these before ... He's been rebuilding trannies for 15 years ... Anybody seen Mike?

11H .... I bow to your greatness ..... man the knowledge you have .... I wish I had one 1/10 the knowledge you have with the information you share on the boards here .....

"GM was not initially happy with this product because it adds a tremendous amount of protection to the transmission and would reduce the transmission failure rates."

I would think that a majority of the transmission repairs done on vehicles once the warranty is up, are done at outside tranny shops, not at the dealer. If GM or any other manufacturer designed their trannies to fail prematurely, the only thing this would create would be warranty repairs, which would cut into the bottom line profit down the road. Besides, repair work is a money maker for the dealers, not the manufacturer. So I think this statement is bunk.
Think I'm in 11H's camp on this one. 4-5 years ago I spent a day with the guys at Level 1 transmission in Western NY while they rebuilt my son's blown-up '95 Mustang GT AODE transmission and turned it into a kick-butt street/strip tranny. Modern automatic transmissions have a series of internal clutch-packs that are non-adjustable. There is a series of clutch packs for the 1-2 shift, a series of clutch packs for the 2-3 shift, etc. Friction between the clutchpack components during everyday operation creates the minute organic and inorganic particles that get captured in the transmission filter and/or the magnet(s) in the oil pan. As 11H mentioned, oil filters are pleated for a reason; ie to create more surface area. Increasing surface area allows the filtration of a larger volume of oil w/o clogging the filter and starving the tranmission componets of fluid. Everyone should also remember the transmission fluid is continuously forced through the filter in the transmission so it is capturing the minute pieces to whatever micron size it was designed to filter. The screen on the Airsept is only going to catch chucks. The biggest enemies of automatic trasnmissions are excessive clutch pack slippage (slow, soft shifts) and heat. This causes rapid and excessive clutch pack wear and when that starts to happen, you would see biggie pieces/parts that would get captured in the screen type filters. However, by then it's too late anyway. In my son's case, he had installed a supercharger on his Mustang and had 3.73 gears and fat sticky tires. Running the car hard on the street generated a lot of clutch pack slippage and heat which caused the friction disks to eventually fail. Level 1 installed HD Rabestos clutch pack components, reprogramed the oil flow in the throttle body for crisper shifts. They also advised installing a transmission oil cooler and using synthetic oil. I did as they recommended and my son never had a problem thereafter. Moral of the story, save your money on this unit. You'll be much farther ahead changing your oil/filter on a regular basis. If you're doing a lot of towing/hard driving ,add an external oil cooler and use synthetic transmission fluid.
Sounds like some very valid points have been raised. Now I'm thinking twice about keeping it on. If I get any more info I will pass it on.

You can send it to me, XRover. ;)

I dunno... ?I'm not worried about the valve side of things very much. I don't work with these in and out like 11H does though.

Doesn't our engine's oil system has two of these type valves? ?One in the pump to limit pressure, and one in the oil filter that opens if the filter becomes excessively clogged. ?They seem to be fairly reliable.

How much fluid flows through these cooler lines? ?I don't think it was a heck of a lot, right? ?What pressure do they operate at?

My opinion is that a little extra protection is better than nothing. :)
Regarding the size, the whole unit looks to be at least two times the diameter off the tranny line. If we could get some specs on the ID/OD's of the valve and the tranny line, we could hash out some numbers to see the general size of the area of the tranny line itself, vs the 'go around' path of the valve...

If they're close, then we should worry... if not, then maybe the sharp angles and spring won't matter much?
Well here's an interesting update !!

I went back to my dealer today and asked Pablo to remove the filter and put it back to stock. My main reason for this was that I noticed that my Transmission temp gauge was reading higher then normal by about 10 degrees. I was concerned that maybe for some reason the filter was restricting flow and after all the previous posts I was getting scared.

Pablo first ran the Tech 2 diagnostics to see what the actual tranny temp was compared to my gauge and also to check for any codes. At idle, the trans temp was 168 degrees and there were no codes.

I told him that I wanted to remove the filter and run the truck on the road to see if my temp changed. Pablo removed the filter in front of me and put the original fitting back on.

As he and I began talking about my concerns about the safety bypass possibly not working in time of need and any possible restrictions, we looked inside the filter to demonstrate the bypass.


We carefully removed the metal and examined it.
To remind you all, I had the Tranny system flushed yesterday and then the filter was installed. I have only driven the truck for about 20 miles.

I have scheduled for first thing tomorrow morning the truck going up on the lift and the trans pan dropped for examination of what might be going on with the metal shavings. All that is being done under my GM warranty due to what this filter caught.

I know for a fact that the filter was new and clean when it was installed because I was holding it during the installation.

I drove home from the dealer today with the filter off and the hose connection back to stock.

My trans temp remained the same temp as when the filter was installed so the filter was not the issue.

I will post what is found after the pan is dropped tomorrow.

Doesn't our engine's oil system has two of these type valves? ?One in the pump to limit pressure, and one in the oil filter that opens if the filter becomes excessively clogged. ?They seem to be fairly reliable.

The series of engines that specs the PF-59 filter has a by-pass valve built into the engine ... It is not in the filter ... GM for whatever reason has chosen to rely on THEIR by-pass design incorporated in the motor vs. the various filter manufacturers own designs and specs ...

Yes, the trucks do have a bypass system; if the filter has too much differential pressure in relation to where the bypass is set to open, then the bypass valve will allow full flow of dirty oil to the engine ... But understand you're also talking huge pathways incomparable to the gadget we're talking about here... If you look at the pic, and understand how brass fittings/couplers are normally constructed, you will estimate that when the unit is new, maybe it slows/restricts flow 10-15% ... But clog it, and it may restrict 50% or better if the screen is clogged ... Just estimate the filter being say 1/2" ID ... If the screen is 1/4" ID, then that leaves about 1/8" of area around the screen seat on all sides that the fluid has to travel making four 90 degree turns and accross a spring that will ultimately invade that 1/8" of space...

I don't care what the measurements are, we can surmise it's significantly smaller than the outer dimensions... Internally, it looks fairly robustly constructed with brass... This robust construction takes up space ... ?:6:

Personally, you guys do what you want, but I won't feel fuzzy knowing there's a small filtering apparatus in line with the life blood of my tranny flowing through it, and the fact that it's there even when new restricting flow... Maybe in 10,000 miles the screen gets 50% plugged by debris; now I'm relying on a narrow path by-pass valve which who knows how much restriction it allows ... And ultimately, if it clogs, no flow ... I would rather have a 1/8" piece of junk flow through the cooler, return line, and eventually get caught by the magnet or the filter ...

I tell ya, I would be pulling that thing every oil change ... LOL !


I hear ya 11H - just trying to cover both bases.

I'd like to get one of these in my hand to see what size everything is.

The screen reminds me of the type you'd see in a garden hose. Granted, water is thinner than oil... by how much, I really don't know... but they flow fairly well, and they are much smaller in diameter compared to the garden hose itself.

That's interesting about the filter/bypass valves. Thanks for the clearingup.
I agree with 11H on this thing. I have not seen or heard anything about them. It does look like a well constructed item and I like the fact that it looks like its suppose to be there. I would be concerned about the flow rate too, there is just not enough surface area to collect much and you would have to check and clean it often, but on the other hand if you have that much metal floating around, you've got a bigger problem. :rolleyes:
I took the Av in this morning to my dealer. We dropped the Trans Pan and did not find any unusual amount of debris. In fact, it was pretty clean. New filter and gasket and it was back together.

I had them reinstall the filter after my concerns of flow restriction and or by pass failure possibilities were addressed and explained to me.

The filter has undergone much testing by special labs that were independent of the mannufacturer. The Filter is also warrantied against any failure of the transmission caused by the filter. The testing and specs can all be obtained through Aisept.

I am very happy to know that I can just pop the filter off and look at it and know if anything unusual is happening with the Transmission oil. Obviously the magnet on the pan does not collect all metal particals as this filter has proven that.

My dealer stocks and installs the filter and believes in it's value 100% and so do I..