Topic: 4.0 tb question

[93yjFirstJeep]

Does the 4.0 tb necessarily have to come off of a wrangler or could it be another jeep like an xj or zj?

[roksld13]

as long as the bolt pattern lines up it should be fine, i got my tb off a 99 wj for my 97 tj. hope that helps!

[sharpxmen]

got mine off a Cherokee, not sure what year but worked just fine - just needed to swap the IAC and TPS from mine.

[OH-YJ]

got mine off a Cherokee, not sure what year but worked just fine - just needed to swap the IAC and TPS from mine.

X2. I got mine off of a Cherokee as well. And make sure you swap the IAC and TPS from the 2.5 to the 4.0. I failed to do this and it resulted in unwanted revving. Live and learn.

[Bounty Hunter]

You can use '91-'04 TB's off a 4.0L engine, but for '96+ you will have to put a cap on the MAP sensor vacuum port at the base.

[stan98tj]

X2. I got mine off of a Cherokee as well. And make sure you swap the IAC and TPS from the 2.5 to the 4.0. I failed to do this and it resulted in unwanted revving. Live and learn.

does that have to be done on a 62mm TB...maybe thats why im gettin some weird revving in park and  neutral? i think i should bore out my intake port to 62mm as well..should make a difference right?

[jdarg]

If the intake isn't bored to match it will almost certainly hurt performance because of the airflow being disrupted by hitting the top of the manifold along the edges.

Matching the intake opening and even radiusing the intake opening are worthwhile if not necessary for this mod to help.

[Bounty Hunter]

does that have to be done on a 62mm TB...maybe thats why im gettin some weird revving in park and  neutral? i think i should bore out my intake port to 62mm as well..should make a difference right?

Regardless of using a 4.0L TB or a 62mm TB, you should use the sensors and IAC housing from your stock TB.

[dwtaylorpdx]

ANother note, if you don't match the intake to the
throttle body it can stick the throttle slightly open.

Dave

[Bounty Hunter]

ANother note, if you don't match the intake to the
throttle body it can stick the throttle slightly open.

Dave

How?  The throttle plate is not close enough to the intake opening to have any interference.

[sharpxmen]

How?  The throttle plate is not close enough to the intake opening to have any interference.

x2, it won't get stuck





the diameter of the butterfly in this one is 60mm, not accurate but close enough for an idea, the measurement shows the max width of the butterfly at the bottom face of the t/b (smaller than the 2.5L opening so like bounty hunter said, is not wide enough to get stuck.