lobuxracer

iTrader: (2)

Yes indeed you are right. The 3S-GTE and the 5S-FE have this same oil/coolant heat exchanger in 1991!

Yri

An old design I see! XD

lobuxracer

iTrader: (2)

There's not a lot of magic in a heat exhanger especially liquid to liquid. Maybe it would be better if it were made of a lighter metal, but that's about as far as it gets.

CSpecISF

Does anyone know the thread size of the union bolt in this diagram? Is it M20, M22 or 3/4-16UNF?

lobuxracer

iTrader: (2)

There are no SAE threads on any Lexus. Not sure if its 20 or 22mm, but it definitely isn't SAE.

CSpecISF

The 1IS and all SCs, along with many other Toyotas used 3/4-16UNF oil filter threads, so it's a possibility.

I'd check it myself, but don't want to disassemble things purely to check thread dimensions if someone already knows it.

Jeff Lange

iTrader: (1)

Most Toyota/Lexus models with spin-on filters use SAE thread sizing, it is the same as Ford. Ditto for Denso A/C threads which are AN sizing. Stuff like oil pressure sensors are usually inch-sized BSPT as well. The oldest model I can think of that uses this style of heat exchanger for the oil is the 85 Pickup/4Runner Turbo. Older versions of the bolt would definitely have been 3/4-16UNF.

That said, for this particular bolt, it isn't listed separately so you'd have to measure it most likely. I expect it's either 3/4-16UNF or M20/M22x1.5, not sure which is more likely at this point, but if I had to guess I'd say M22.

Jeff

mike33

iTrader: (1)

When doing research on putting together an oil cooler kit I came away with the impression that it is a 3/4-16UNF. Hurtado installed
a Mishimoto kit in his build thread, that kit comes with both a M20x1.5 and 3/4-16UNF, I would message him to see which bolt he used.