NewHilux.net

OK. I know this topic has been done to death but......
I've been reading through all the posts about this and there seems to still be some dispute about whether to use a 30 micron prefilter or a 2-5 micron secondary filter.

As I understand it the 2-5 micron secondary filter will do a better job of filtering and is better matched to the injectors hole size but MAY result in premature pump failure and fuel pressure warning lights etc.

Obviously the 30 micron prefilter is to remove the larger particles and can separate water, but wont to anything to stop smaller particles.

Some filter Kit manufactures promote secondary kids for our D4Ds and other recommend filter kits. E.g. Diesel Care promotes a Secondary Filter Kit while western Filters recommend a Prefilter kit (Fuel Manager).

Given a mate of mine just paid put for a full engine rebuild after DIRT (not water) found its way through the OE 10 micron filter I'm leaning towards a secondary filter but am worried about the pump failure/pressure issues.

Who here was either setup and what have your experience?

Secondary filter 2 micron, never had an issue with flow even when I had a chip and the safery relief valve on the rail released causing a low fuel pressure code.

The same as above. Had mine for several years with no problems. I think Baileys Diesel website has a post about this and recommend the eom filter being used as a primary filter. cheers.

Same as above. Secondary filter Fuel Manager 2 micron, never had an issue with flow or errors and has a Steinbauer chip.

Prefilter with 10micron filter and oem inplace as main, no issues an steiney also

Hellbound wrote:Prefilter with 10micron filter and oem inplace as main, no issues an steiney also

Isn't that just two 10 micron filters in line? (oem is 10 micron also).
I don't understand the benefit in that.

I have fitted a fuel manager 2 micron secondary filter to my 2009 Hilux and have had no issues with engine performance. The genuine filters are said to have a 300 lt/hr flow rate which is plenty.

I bought Diesel Distributor's Direction Plus secondary filter kit. What a disappointment: the bracket did not fit properly so I had to modify it (bolt holes didn't line up properly and the forward corner of the bracket fouled with the fuse box).

The 3/8 fuel hose supplied with the kit was a bit of a loose fit onto the engine fuel pump. Despite tightening the hose clamps nice and firm I had to prime the OEM pump every time the car had been standing for more than about 15 minutes. I eventually discovered that air was getting in here. I bought some 5/16 hose which solved the problem however it was really difficult to get onto the brass fuel filter 'nozzle' as the fittings in the kit were for a 3/8 hose.

I subsequently contacted 2 other suppliers. One advised that they supply 5/16 hose in their kits and the other advised that they supply both 3/8 and 5/16. Worth checking before you buy.

The problem here is that both the inlet and outlet nozzle sizes on the Hilux fuel filter are 10mm, but the nozzle on the fuel pump is 8mm........good going, Toyota.

Therefore the OEM fuel hose with 10/8mm ends is necessary.... Good one Toyota!

Otherwise use the 5/16" and force fit... Hmmmm not good engineering practice

Or use two different hoses and a barbed reducer ..... Messy resolution

I have a prefilter 10micron and the OEM main filter... In my view the best solution because the prefilter does the water and frogs from your tank, and you can visually check for gunk, then the OEM main filter is the final safeguard. I have not had problems until recently when the OEM filter light stayed on solid after 55k klm's (reduced flow warning light) and a new filter fixed it. Now I need to change the prefilter out for a new one but because it's 10micron it is still filtered but even better because the filter is somewhat blocked it filters even closer to OEM spec. That's precisely why I prefer this arrangement. Belts and braces approach... Prefilter for big stuff and water and then OEM for fine stuff.

I might also add, I have had water in fuel which was visible in the prefilter but didn't get to the OEM, then the OEM drained and found clean!

Also, when the OEM filter was changed after 55k klm's it had the fine black stuff on the filter as to be expected after 55k. That's how filters work!

Post script: does anyone know what the OEM filter is? I understand it is 2.5 micron but I'm interested to know the TRUTH from a reliable source.

Gipsy wrote:Post script: does anyone know what the OEM filter is? I understand it is 2.5 micron but I'm interested to know the TRUTH from a reliable source.

The chatter has always been around 7.5/10. Never heard of 2.5 OEM, and don't think 2.5 is correct.

However, you did ask for reliable and the closest that I can get is that Donaldson's replacement for the OEM is specified at 10.
Ryco don't specify Micron rating for their replacement for OEM, but you would have a better chance of getting a straight answer from Ryco than Toyota dealerships.
I can't see Donaldson or Ryco selling a relacement that had less efficient filtration than the original, but who knows.

https://www.berrimadiesel.com/pre-filter-kits

This from Berrima Diesel suggests 2 or 5micron.

https://www.baileysdiesel.com/on-highwa ... or-damage/

Bailey's say 8 to 5 micron

Then there's this:

Spoke to 5 different WA Toyota dealers yesterday, got 3 different answers on fitting pre-filters and effect on warranty...do it, don't do it, don't know....

View from the 'do its' was pre-filter is (a) necessary, (b) won't affect warranty because it's upstream of OEM filter, (c) cost effective insurance. Both these guys were technical workshop foreman/Service manager types. Was surprised to be told that the OEM filter on MY12 and MY14 models (with water trap, sensors, alarm) is 0.5 microns I thought it was more like 2. Anyway for the pre-filter the Stanadyne FM100 got the most airplay, that's what they are fitting when a pre-filter is requested by the customer, they werent using with the Racors. They are getting the kits with pre-made brackets, ancillary stuff. They won't warrant the install because it's non-Toyota parts. Key thing for in-warranty vehicles is that the filter must be placed before the OEM filter and most very definitely not after it. After warranty you can do what you like as long as the required flow rate is not restricted.

Hmmmm seems the Toyota guys care the LEAST reliable reporting .5 micron.... So who REALLY KNOWS?