A dual NON-bypass filter setup? Worth it?

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I have seen plenty of the bypass setups but what about full flow dual kits? I drive about 20k a year and want extended drain intervals so I don't have to crawl under the truck in the winter. Would a dual full flow be better, worse, or the same as a dual bypass kit? Who makes the best full flow dual kit? My truck is a F350 crew cab if it matters.
 

JHZR2

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Id be worried that this would cause irregular flow patterns and effectively only use one filter if they were paralleled, or cause excessive pressure drop if they were put in series. This could induce extra pressure-relief flow, etc. I'd go with a real bypass system to optimize filtration, or go with an oversize filter in a remote mount, etc.
 
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I ran a full flow dual remote bypass for years on my Volvo turbo. Too my knowledge these are all parallel flow units and cause no flow issues that I know of....the pluses are two large filters can add a decent volume, cool the oil, longer filter life, etc...the minuses may be with a very viscous oil in a cold climate flow might be a problem (longer warm up), maybe problems if you have a very weak oil pump(?)..... I used a Summit cast mount, but most are all about the same.
 

JHZR2

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was the bypass dual filter, or was the primary full-flow filter "dualed up"? If you use full flow elements as a "bypass" I don't see an issue, but I question if youll actually get full use of two full flow elements in use as a full flow filtration system. Slight differences in pressure drop will create preferential flow situations which will under utilize one filter.
 
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You must have seen these set-ups in catalogs and such: http://www.summitracing.com/parts/SUM-G4986/?image=large So it's a "dual NON-bypass filter setup" as the OP says. I probably shouldn't have used the word "bypass" in my initial post. It's just a simple relocation of two instead of one primary oil filter. I'm sure initially one filter flows a bit easier than the other until it gets a tad more restrictive then the flow goes to the other....but this should not be a huge problem. When I dissected both filters they both seemed equally used.
 
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 Originally Posted By: JHZR2
was the bypass dual filter, or was the primary full-flow filter "dualed up"? If you use full flow elements as a "bypass" I don't see an issue, but I question if youll actually get full use of two full flow elements in use as a full flow filtration system. Slight differences in pressure drop will create preferential flow situations which will under utilize one filter.
Wouldn't that work like a feedback system and be self rectifying? In other words, wouldn't the over-utilized filter, having more flow, load up faster? Then when the over-utilized filter gets loaded, it creates more "resistance", causing the oil to divert to the lower resistance less utilized filter. I agree with your comments on parallel vs. series. In a sense the filters would operate like resistors in a circuit. If you run them parallel, they half the rated resistance and if you run them in series, they double the resistance.
 

dnewton3

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"F-350" doesn't tell us much. Older 460 or 351? Older 7.3L? Newer 5.4L, 6.8L? 6.0PSD? What type servity factor? Regarding the filters, two parallel full flow filters likely would last about 20k miles, because conceptually a single good quality filter such as Wix could probably go 10k miles. Since the incident rate is cut in 1/2 per filter when you double the quantity, it's plausible. The question really becomes not so much about the fitlers, but can the oil last that long? If dino, I rather doubt it. If synthetic, it's possible. One downside is that (with any ancilary system), you've got extra plumbing, etc to deal with. More hoses and hose clamps means more ability to leak or fail. The upside to this type system is that, after the initial purchse, you'd still be able to get decent quality, inexpensive filters. With a true bypass system you end up with proprietary filter elements that cost a great deal. You probably won't like a TP bypass filter, as they are maintenance intensive; ruled out by your desire to not OCI in winter. But a dual full flow is cheap after the initial cost. Increases the sump size too, which slows maturity and adds to cooling affect (can be both bad and good, depending upon point of view). What about a EaO filter? I realize that they are not warranted with anything but their own brand for the 25k miles, but they could possibly fill the need. I guess that you'd be best off experimenting, and letting us know the results. I don't think that there is any clear-cut "best" choice here. Some amount of tinkering and value-driven decisions are going to have to be made by you. Heck, we'd all like bypass-filter results from full-flow fitler systems, but (at least at this point in the lubricant world), you can't get there from here. Somewhere along the way, you're going to have to pay the piper. I see several options: 1) change oil 2x a year at 10k mile intervals (spring/fall = winter avoided) with quality synthetic and filter 2) change oil 1x a year with high end synthetic/filter (most notably Amsoil due to their paired product warranty) 3) run a multi-full-flow-filter set up, and do UOAs, probably with synthetics 4) run bypass with UOAs, likely with synthetics I highly suspect that if you want extended drains, you're going to have to get into the paired Asmoil products for their warranty, or go with a bypass system.
 
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 Originally Posted By: ScubaCat
I have seen plenty of the bypass setups but what about full flow dual kits? I drive about 20k a year and want extended drain intervals so I don't have to crawl under the truck in the winter. Would a dual full flow be better, worse, or the same as a dual bypass kit? Who makes the best full flow dual kit? My truck is a F350 crew cab if it matters.
I've done almost all of them except the Amsoil combo/dual. The Permacool dual works ..but it's cheap. Mine seeped ..not a big issue. With 20k a year you're just outside of my limits for anything other than an EaO filter for just your regular filter. Dual you could probably use PureOne or anything really. 15k for a filter with up to 15k/year works for an every other FCI/OCI deal. You need an extended drain oil for 20k/one year. If you're not into that, you're already at a 6month OCI with a 10k synthetic. That's with or without the dual mount. You can get away without filter changes with the dual mount ..but not without an oil change. Yes, any flow bias, which should only be in the most minor of differences since the pressure on either side of the filters should be somewhere in the micro-inches of W.C. of each other, should be self correcting. If anything, the lead filter will stay just ahead of the lag filter in loading ...or so my reasoning tells me. You do add complexity ..but nothing that requires too much tending. If you want something other than a Permacool, get a Dual Guard Amsoil mount and also order the threaded inserts for 3/4-16 filters. Then you can order a bypass filter if you want to later. You won't get the biasing valve that the dual/combo's do ..but that's not all that big of an issue, imo. Try my future setup before I do. Get a Dual Guard (bmk22) and a Permacool sandwich. Leave a full flow right were it is. Run two bypass filters of any size you like (up to 2 quarts each in added capacity). The Permacool sandwich should limit the real size of the sump based on temp/visc by maintaining 2psid across the bypass filters. I think you could get over 2 years out of the filters ..maybe more. It all depends on how much money you want to exchange for convenience. You can do this, btw, with the Permacool dual mount too. Wix has 3/4-16 bypass filters and dual combo bypass/fullflows. The Sandwich will provide relief for the dual mount, and you'll still retain your filter bypass for whatever full flow filter you choose. That would run you about $100+ connecting hardware + filter costs. There are a few ways to skin this cat.
 
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20k is pushing it on a PCMO without bypass filtration. The dual full flow filters should have no problem going 20k but you'll have to change the oil....only a UOA will tell you when and give you the answer. Install the dual full flow with 2 quality filters(napagold, M1, Ams, RP...or a combo) and do a UOA at 10k. Pick a higher TBN full synth HDEO for TBN retention and see what happens. An engine in a good state of tune, all highway driving, regular oil topoffs(refresh),.... and a 20k OCI might be possible.
 

dnewton3

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Again, knowing the engine configuration might help. Not so much as being able to "yes", but more so to say "no way". For example, 20k miles might be possible on a moderately used 5.4L that does lot's of highway miles, and is not loaded heavily, using synthetic and a dual full flow???? But, I'd never suggest to go 20k miles on oil on a 7.3L PSD without bypass filtration. To me, 20k miles seems right on the edge of reason, and tips towards "probably not viable". Not because of the fitlers, which doubling up Full Flow can probably get you to. It's the oil which is really going to be a stretch. Let's not forget that sump maturity and capacity play greatly into this. Depending upon engine configuration, he could get a deep sump pan, plus dual full flow filters, and double his sump capacity (for example if the engine was the old 5.8L or the 7.5L, there are lot's of aftermarket pans to greatly increase the sump size). Doubling the sump capacity, along with two quality full flow filters might get him there. But it all comes down to a cost/benefit ratio. Unless money and time grow on trees for you, it always comes down to the triad of time/money/effort. Sort of like Gary's filter triangle ... The only real viable sitations I see are either paired Amsoil synthetic/Eao, or bypass filtration.
 
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Here's a "what-if?" What if you took this parallel filter mount and installed one "regular" filter, with an average micron rating, and one very fine spin-on filter, as you might install in a bypass setup, side by side. Obviously, the less fine filter would get most of the flow, but some would be directed though the finer filter as well, thus acting like a bypass. As the "primary" filter loaded up a bit, even more would go to the finer filter as time went along.
 
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As Dave says, the oil is the weak link here. A conventional, under ideal conditions can go 13k with a GM OLM. We've seen that before, but that's a far cry from 20k in whoknowswhat? service with just one quart added to the sump. I'd say you're at 10k with the dual filters. You can probably skip the filter changes in the OCI at the 6 month mark. As many have suggested here, get a UOA at your current OCI just to see how your current sump endures your service. Once that's figured, you may be able to extend it beyond what you currently do. After everything is shook out, then you can purchase an oil that may give you more longevity like one of the Amsoil products. It may be the case that no dual mount is required if the service is light enough. We often imagine severe service more than it exists.
 
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 Originally Posted By: Gary Allan
[quote=ScubaCat] order the threaded inserts for 3/4-16 filters. There are a few ways to skin this cat.
You can order the threaded adapters on ebay,don't remember how much.
 
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3/4-16 threaded inserts are common. 3/4-16 to other threads (5/8-18/1-16) are not. TMVTAYLOR (or is it TVMTAYLOR) on ebay has good sources for those adapters. He's not cheap, but it's a limited niche item ..so there's not much to complain about.
 
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