1996 GQ TD42 Turbo oil filters - is one a bypass?

[Ricor]

I am doing my first oil change on my new 1996 Patrol (Safari actually) TD42 Turbo.

How do I know if I need a full flow and a bypass filter or 2 full flow filters. And if I need a bypass which one is the bypass (The 2nd one I assume).

Also, oil recommendations?

Thanks

[jff45]

Neither of the TD42 filters is a “bypass” filter. They are all full flow filters.

If you have the oil cooler body that has a 1”-12-UNF thread for the front filter it will typically use a Z416 or equivalent filter and the fitting on the oil cooler body itself will bypass a small percentage of the filtered oil straight back to the sump.

Most of the filtered oil from that front filter will mix with the filtered oil from the rear filter and go through the engine’s lube passages.

[Ricor]

OK thanks. The internet is getting confusing with more and more conflicting stories. Real people is the way to go. I love this forum.

[jff45]

There's a slot on each side of the filter thread where a small percentage of the filtered oil passes and is diverted into the passages shown in the pic which flow directly into the sump.. hence the term "bypass"


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[Ricor]

Yes, that is what I have. So what filters do i need? What came out is AY100-NS010 (rear) and AY100-NS012 (front) but they seem impossible to find here in the US.

Both are Pit Work filters.

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