A650F 5 Speed for 1FZ (1 Viewer)

[HDJdreams]

This thread starting to get too wordy like it’s predecessor. Time for more pics and tech!

Hard to find the right angle for a photo, but the A343 pan is much deeper than the A650, thus it sits higher and at an angle compared to A650 when both are sitting next to each other.

 

[HDJdreams]

This could be a short journey...

Sad but true. I downloaded both transmission FSMs.

Already found a show stopper

 

[HDJdreams]

A343F, the No. 2 One way clutch is INSIDE the main housing. The tail housing is “empty”.

 

[HDJdreams]

A650E, the No. 2 One Way Clutch is OUTSIDE the main housing and in the tail housing.

 

[HDJdreams]

Game Over

 

[Dragos80]

What I would hope to achieve most by 5 speed swap is to find a gear between the A343Fs 2nd (1.53) and 3rd (1:1). The A650 is awfully close at 1.42, hopefully it still makes a difference.

YES!!!

And when also consider the drop from 1st to 2nd on 343, how awfully low the RPM goes, it makes so much sense.
Then if tow something you would know shifting from 1st to 2nd comes with a lot of prayers to keep it moving.
That's the biggest let down with this 343 tranny.

 

[Dragos80]

“You would have a very short 1st gear which would redline the engine each time start moving from a standstill.”

Not even close.

The current crop of 8 and 10 speed automatics have a 4.7-5.0 1st gear.

I drove a A750F with 3.5 1st 4.1 axle gears (14.4 total ratio) on 31” tires for years works great! Same for 6L80 Tahoe, 4.03 1st and 3.42 axle (13.8 total ratio) on 31s.

I was referring to 3.52 plus 4.88 on 1FZ.
It's over 60% reduction in gearing which would translate in much higher RPM.

Let's not get side tracked here.
I can't thank you enough for picking this project up and doing something meaningful for all of us.

 

[Dragos80]

Game Over

Oh s***!

 

[cjmoon]

Game Over

This is how the a750f ended. parts have to be made. It’s possible but how much would parts cost. Would others buy such an expensive part. I’m still thinking about making a Bell housing and converter adapter to make the a750f work but it would be an expensive part and would take years to break even. Let alone turn a profit.

 

[Dragos80]

We just can't have all the nice things we want in these trucks.
Either impossible to do or prohibitively expensive.

 

[mjosoba]

Sorry @HDJdreams i prob did it wrong. I was asking @cjmoon about his plans. Irrelevant now I guess. Sorry man. Appreciate the efforts.

 

[cjmoon]

Game Over

Been there done that. On the a750f route that was talked about. Glad you did it and detailed what this family of transmissions shares and differs. Still have a trans in my basement. Ended up stealing a speed sensor so I got something put of it. A very expensive speed sensor and shelf space taken up. Oh well. Thats what it takes to make progress. Way more failures than successes if you look at the details.

 

[HDJdreams]

You mean one of these

 

[HDJdreams]

Too bad it has wrong transfer case.

 

[Obrokoff]

Too bad it has wrong transfer case.

You need a750f from uzj/hdj100. It has 19 spline output shaft.

I have Lexus gx470 a750f for rebuild to hdj81 and hf2a. It needs change 23 spline output shaft to 19 spline. Bell housing fits good

 

[Woofythewolf]

Thank you for investigating the A650f. It's hard to learn and make progress without at least a few mistakes.

 

[bugsnbikes]

Um... 1fz /5spd.

FJCO 1FZ-H55F Bell Housing

 

[Dragos80]

We're after an automatic solution, not manual.

"The FJCO 1FZ to 5-speed Manual Transmission Bell Housing is the solution for enthusiasts who have dreamed of a manual transmission behind their 1FZ engine!"

 

[bugsnbikes]

U lookin for better gearing spread ? Or just weaker transmission options than a442?

 

[Rivman1243]

Here's a explanation of how they got an extra gear in that trans and why the number 2 clutch is in the tail housing.

Auto Trans interchangeability - ClubLexus - Lexus Forum Discussion