Differences between a GS300 2JZGE and the IS300 2JZGE
Spent the last weekend swapping a 2JZGE from a gs300 into an IS300. Made a little list of differences and info that may help someone else.
We believe you can use the GS300 loom for the Is300 however we swapped the loom as the alternator charge wire had been cut from the replacement engine.
Waterpump, tensioners and pulleys were all the same.
The power steering res is slightly different on a GS300 and has a valve with some vacuum tubes running to it from behind the cam gears. We swapped the IS300 one across.
Sump spacer missing sensor in oil pan
On the lower front LHS of the engine, with the timing at the front, on the IS300 there is a oil level sensor. It uses a 4 bolt plate and reads when the oil level is low. It uses a two pin plug and can be jumped with wire to get rid of the light. The GS300 motor didn’t have the sensor or even the bolt holes, it would require drilling and tapping the sump spacer plate to install one so we’ll just jump it out and not worry.
Valve cover mounts are taller
GS300 vvti valve covers have taller mounting points and use taller studs and bolts to secure them. The mounting pattern is the same but if you’re trying to put them onto an IS300 then you’ll need to swap the studs over from the GS300 and use the longer bolts.
Rear water neck at back of engine at top sits lower
Not a major thing but one to note the neck going into the head between the valve covers right at the back of the engine is comes up slightly more on the GS300. We got the old hose to fit no worries but if you were going the other way the hose might be a bit short.
Oil filter mount doesn't have cooler
The oil cooler on the IS300 has a coolant heat exchanger while the GS300 does not. They use the same union bolt mount with the pressure sensor on the end and looks to be the same filter bracket but just missing the cooler.
Doesn’t have a heat exchanger below the water pump
Also GS300 doesn’t use a exchanger for the auto trans but used hardlines which run to the radiator. The GS300 pipe runs straight off the back of the water pump and up to the heater core lines on the firewall. Good part to get for an IS300 to clean up that section.
Water neck to radiator on head different angle
This one caught me off as I wasn’t expecting it but easily fixed. 3 bolts/nuts and the upper neck was off and swapped over. The GS300 neck angles upwards and is a little bit shorter, while the IS300 neck comes straight out from the head.
