Why exactly does a 3b tranny have a long input shaft & gas tranny doesn't (1 Viewer)

[TOBASH]

OK, I have asked some questions about this, but I am having trouble wrapping my head around the whole thing.

If the regular gasoline H55 has a shorter shaft and fits an H engine, why can't the bell housing be modified to fit a 3B and the redrill the flywheel to accept the clutch and move the tranny mounts to accept a shorter tranny.

I just do not understand why a regular gasoline tranny cannot be mated to a 3B with minor adjustments to the flywheel and tranny mounts and bell housing (unless the starter position is in some weird place, and even then the 3B bellhousing can be shortenned... No?).

Best,

T

 

[77cruiser77]

It's weird I know and I don't know exactly why Toyota did that. It does seem that the 4 cylinder engines got one length and the 6 cylinder got a different length I think even up to the current 1HZ and 15B-FTE. I don't know if it's because of the bell housing or the way the inputs are made on a 4 cylinder are that much different than a 6 cylinder gas or diesel.

If you are asking because you have a H55F for a 6 cylinder already and want to put it in your 3B why not just change the spline shaft?

 

[BreckenridgeCruiser]

I'd bet it has to do with positioning the engine for weight distribution... Just a guess since Toyota does such a good job of trying to reuse parts that there has to be an engineering reason for the difference.

 

[Dieseler]

Is the depth of the bell housing different on the two types of engines I have never thought about this before I have a 3B with a H55 as well as a couple of 60s with the H55 one being gas and the other being diesel.`
Does the long shaft extend further into the crankshaft or is to make up for a deeper bellhousing.

 

[TOBASH]

Is the depth of the bell housing different on the two types of engines I have never thought about this before I have a 3B with a H55 as well as a couple of 60s with the H55 one being gas and the other being diesel.`
Does the long shaft extend further into the crankshaft or is to make up for a deeper bellhousing.

The depth from the pilot bearing to the splines is the same, so I would think it does NOT extend in further.

 

[Wedg3]

If you are asking because you have a H55F for a 6 cylinder already and want to put it in your 3B why not just change the spline shaft?

If so, I have a H55 B fine spline input shaft spare in exchange of a coarse spline H55 input shaft.

In other way, I think that this is because the B engine is smaller then 6cyl. an sit 1 1/2'' near front. The bellhounsing is 1 1/2'' longueur I think so the drive line is at the same place then the 6 cyl. Why fine spline... ? that I don't know.

 

[TOBASH]

It's weird I know and I don't know exactly why Toyota did that. It does seem that the 4 cylinder engines got one length and the 6 cylinder got a different length I think even up to the current 1HZ and 15B-FTE. I don't know if it's because of the bell housing or the way the inputs are made on a 4 cylinder are that much different than a 6 cylinder gas or diesel.

If you are asking because you have a H55F for a 6 cylinder already and want to put it in your 3B why not just change the spline shaft?

No, I do not yet have the 5 speed tranny, but I suspect this is for ballance too. Given that I'll be placing a 12,000 lb. winch on the rear bumper, I think ballance issues will be sorted out.

I may indeed try going the gasoline tranny way, as if it can handle an H Diesel engine it should be fine with a turbocharged 3B.

Just to sort out the confusion, I already have a 3B with a H55 ready to plop into my BJ-44. It is just that I laid down some cash for another landcruiser that I will be eventually swapping to Diesel.

I may decide to use the H55 Diesel for the second truck and experiment with the BJ-44.

A shorter tranny might make up for shifter reallignment issues and for axle length issues that come with H55's that come out of 60 series trucks.

That being said, ONLY IF THE STARTER MOUNTS LINE UP, so anyone know if there are starter alignment differences b/t 3b and gasoline H55 trannies?

 

[Wedg3]

No it's not. Gasoline engine don't have the starter on the driver side like the B engine. Certainly not the same starter and flywheel. Clutch from B engine is smaller too I think. So nothing from F engine will fit on B engine. For a swap of engine, you need the bellhousing, slave cylinder, fork,clucth, flywheel, starter and input shaft from the engine you want.

H55 from gasoline an d H55 from Diesel is the same internal component except the input shaft so the worry all H55 can handle the same duty like every H42 and H41