How well does 3-speed hold up to 5.3 under "normal" driving conditions ? (1 Viewer)

[logic2]

I have a 72 FJ55
Original drivetrain: F engine with 3-speed tranny.

I have a low mile 5.3 from a suburban that is currently mated to its original 4l60e (2wd trannny).
This is a running/driving engine up until this Friday when it was pulled (all accessories), harness, computer, etc... Although I'll probably replace the factory harness with a stripped down (NEW) after market harness and reflash the ECM.


My long term plans are to find a good transfer case that would work well with this 4l60e transmission and upgrade the entire drivetrain. I know the 4l60e has a centered output and that would would create a little bit of an angle on my rear driveshaft, but I think the FJ55 has a long enough wheelbase to handle it as long as my driveshaft is well balanced and well built.

Point is, I would prefer to do this project in phases to minimize the downtime.

I'm considering to simply replace the F engine and use the original 3-speed tranny and transfer case.

That would require:

-- New 5.3 motor mounts
-- Replace the Flexplate currently between the 5.3 and the 4l60e with a Flywheel that mates up to the 3-speed tranny.
-- Bellhousing Adapter (may or may not be needed, more investigation needed)
-- Clutch / Pressure Plate / Throwout Bearing / Pilot bushing ??
-- High Pressure Fuel Pump

I hope the list above is close, the question is if the Factory 3-speed tranny and txfer case would hold up to the 5.3 under normal driving conditions so that this would only be an engine swap (weekend upgrade) and have it back on the road pretty quick.

This would give me some time to put a long-term plan together regarding the 4l60e and best transfer case to go with it, etc...


Questions:
1. Would the factory Toyota 3-speed tranny / txfer case hold up to the 5.3 ?
2. What would be the best "transfer case" option for the 4l60e and the original "offset" FJ55 axles ?
3. Anyone have a photo of a FJ55 with a 4l60e ? I'd like to see how bad the angle is on the rear driveshaft.
4. Am I making a mistake in the plan above, would you guys do anything different ?


Thanks for any feedback

 

[Rock40]

Hey, that'll be a cool swap, it's been covered several times. My advice is ditch the Toyota 3 speed and retain the factory transfer case. Run a GM465 if you want a manual transmission and you'll driveshaft angles will be close to stick. AA has all the adapters.

I did a Vortec 5.7 swap with an SM420/Rockbox/factory transfer case 15 years ago and it's been awesome. 31,000 plus miles and still going strong.

Guaranteed the Toyota 3 speed will not hold up behind the 5.3 liter, the internals are weak, especially the front input bearing

 

[logic2]

Hey, that'll be a cool swap, it's been covered several times. My advice is ditch the Toyota 3 speed and retain the factory transfer case. Run a GM465 if you want a manual transmission and you'll driveshaft angles will be close to stick. AA has all the adapters.

I did a Vortec 5.7 swap with an SM420/Rockbox/factory transfer case 15 years ago and it's been awesome. 31,000 plus miles and still going strong.

Guaranteed the Toyota 3 speed will not hold up behind the 5.3 liter, the internals are weak, especially the front input bearing

OK, Thanks. That changes my thought process for a quick and easy (engine only swap) - Good information.
It's good to hear there should be no worries about the stock (72) transfer case holding up.

I ran a SM420 behind a 5.3 about 10 years ago in my FJ40 and there were no issues, however this time, I'm thinking about keeping the 4l60e mated up to the 5.3.

--> If the driveline is not at too much of an angle on the FJ55 (should not be...but I'd like to see how long the driveshafts are holding up form those that have done it), I'd really like to try this combo. The 4l60e apparently have the best of both worlds on both ends of the spectrum. A good 1st gear low-end ratio and a decent overdrive to keep your RPMs low at highway speeds.

--> During my research on this Forum, I've also read a lot about the Orion Txfer case having some issues that I would like to avoid, so I'd be curious about other Txfer cases being mated up to the 4l60e. I know there are a few options that will (fit) using AA, but the question is how well they are holding up under the FJ55.

Regarding your combo above, it's a trusted and proven combo and the ACE up my sleeve should all else fail.

Thanks,

 

[lcwizard]

mating such a beautiful motor to an old and ugly transmission would be like forcing a marriage between Jessica Alba and Marty Feldman.....
one of the two will certainly be unhappy... the motor would probably just not start out of spite

 

[65swb45]

mating such a beautiful motor to an old and ugly transmission would be like forcing a marriage between Jessica Alba and Marty Feldman.....
one of the two will certainly be unhappy... the motor would probably just not start out of spite

I wish I could 'like' this more than once.

@ferg and I know a guy from the San Diego Outbacks that put a BB402 in front of a stock 3speed and pulled a travel trailer with it, without issues, for many years. He was very aware of what he built, and he drove with discretion.

Some people build rigs to wheel with impugnity. Others build with discretion in mind. Most of us are somewhere in between, under-using over-built rigs, or over-using under-built ones.

 

[lcwizard]

maybe Mark would know ... how would a 3 speed do at the 6500 redline of a 5.3?
@logic2 , you will very much enjoy that swap if done with the right trans and transfer but I think having a 3 speed behind it would
be akin to running the Boston Marathon in Firefighter's boots

 

[Downey]

If you choose the 4L60E to your stock transfer-case, I have a rebuilt/remanufactured adapter that will save you a couple hundred bucks. Also, send me your snail mail address for a freebie Downey V8 installation instruction manual, file too large to send electronically.

 

[logic2]

If you choose the 4L60E to your stock transfer-case, I have a rebuilt/remanufactured adapter that will save you a couple hundred bucks. Also, send me your snail mail address for a freebie Downey V8 installation instruction manual, file too large to send electronically.

Thanks !

This seems like the best way to go but I have a few questions before I pull the trigger:

It sounds like the only advantage of sticking with my stock (1972) 3-speed transfer case is that I already have it and it's free.
Question is if it's worth it, or should I go ahead and source a good split case from a FJ60?

Thx !

Mike

 

[Rock40]

Thanks !

This seems like the best way to go but I have a few questions before I pull the trigger:

It sounds like the only advantage of sticking with my stock (1972) 3-speed transfer case is that I already have it and it's free.
Question is if it's worth it, or should I go ahead and source a good split case from a FJ60?

Thx !

Mike

I'd stick with it. I've not destroyed mine yet and I'm wheeling it pretty darn hard with a 5.7 Vortec, lots of gearing and ARB's. Doesn't sound like that's what you're going to be doing with yours anyway. Just rebuild it, brace the nose cone (front output) and also brace across the top of the case. You'll be good to go. The braces are available from a MUD member (OrangeFJ45)??

 

[Tin basher]

i would do a case saver on the t case at min
I broke two cases with my small block but I was on 38s and being a @ss with it
Now if you wanted a standard I would look for a nv4500 from a 5.3 truck and adapt the toy case to it
Or stick with the auto you have and adapt your case to it

 

[lcwizard]

For ease ( driveline room ) maybe a NV4500 to a 60 split case.
Driveshafts become a concern with the long powertrains. The short rear driveshaft in a 40 series with a long powertrain adds
some hurdles to the project especially with more than a 2" lift or long travel suspension. Most people will push the rear axle back.
Personally i like a two piece front driveshaft with a carrier bearing to keep the ultra long front shaft safe in an application like that.
It lets you run some serious skid plates under the belly. A 4500 is about the same length as the 5speed cruiser but a lot stronger.
It takes a special flywheel ( Advance adapters ) since the 3rd gens were never mated to the 4500 but coupled to the larger/stronger split case
you'll have a more bullet proof drivetrain. The GM versions are better than 6.3:1 in first gear . The Dodge units are a little better than 5.6:1 . Either are lower geared than the Toyota 5 speeds

 

[logic2]

If you choose the 4L60E to your stock transfer-case, I have a rebuilt/remanufactured adapter that will save you a couple hundred bucks. Also, send me your snail mail address for a freebie Downey V8 installation instruction manual, file too large to send electronically.

Downey,
I am interested.
This adapter does not require cutting down the 4l60e does it ?

Is it just an adapter plate ?

My FJ55 should have a long enough wheelbase that I could handle the length of the tranny in its stock form.

Just checking`

Thanks

 

[Downey]

No, the adapter does not require modifying the 4L60E. What I have was (past tense) a used adapter for TH350 to Landcruiser 3 speed transfer-case (AA #50-7300, sells for $582.90, 5.25" long). I had the adapter casting and shafts sandblasted, and oiled. Then I bought the new pieces from AA to convert the adapter to a 700R4/4L60E adapter (AA #50-8901, sells for $710.82, now 6.75" long). You will need a 2WD 4L60E with 6" long output shaft (with rear extension housing removed). My adapter is in my ebay store for $489.95, but you do not have to buy it through ebay, plus you get a 10% discount on it since I won't have to pay the ebay fees. If you get this adapter from me, I will then provide lots more info on the VSS you will need, and other stuff you will need, and how to hook it all up.

 

[B y r o n]

I ran a stock 3 spd trans and transfer case behind a old school 350 for many years. You have to remember that the early LC drive train was based off the old Chevy truck drive train. It is stout enough as long as you are not overly abusive.

 

[Downey]

But if you trade the 3 speed for the 4L60E that you already have, you: (1) get rid of the non-sycromeshed 1st gear, (2) get a lower 1st gear, (3) get an overdrive, (4) get a torque converter that multiplies torque, (5) get a tranny that handles more torque, 6) get a better hill climber, (7) get an easy way to hook up the VSS to the 4L60E, and (8) don't have to shift gears manually.