LS 6l90 Question (with Integrated Parking Brake)

[portell]

After tons of research my extremely low mileage 6.0 and 6l90 has arrived.

Big question and if any one here has used one, I have a 6l90 with a factory parking brake on the trans.





Has anyone tried to use these? I figured I would ask before I went the traditional slip yoke method

Here is a picture of the motor, its very clean.

[solidaxel]

That's cool!
What are you putting it into, is everything going to fit !!!?

[clinebarger]

The 6L90E looks to be out of a Isuzu N-series/Workhorse Chassis.

Take the Drum off, 4 big nuts & the 2 cap screws, Remove the Cotter Key & Center Nut, Slide the Yoke out (Have a Drain Pan).

I want you to see if there is a Output Bushing? Or is there a Output Bearing?

Then Count the Splines on the Output Shaft, & Measure the O/D of the Yoke where the Seal rides........ Commercial Chassis can use oddball Spline & O/D Yokes.

If you have a Roller Output Bearing.....You CANNOT run a Slip Yoke without swapping out the Tail Housing for one with a Bushing.

Another hurdle you may run into is the Output Shaft itself may not be Fully Splined & Not accept a Slip Yoke, You can remove the Backing Plate & Tail Housing & confirm with posting pictures.

With all that said........It may be easier to source the Correct Output Flange & have your Drive Shaft built with a Built-in Slip, Call the place you bought the Trans from & see if they can sell you the Output Flange....Or give it too you for selling such an ODDBALL unit.

This is ABOUT what the Flange will look like...... http://www.fortwayneclutch.com/index...31-s80726.html

In fact if you want to compare the listed specs to see if it will fit the 4 Studs sticking out of your yoke & the Center Register.....This Flange may work if you supplier wont help. And trust me you DO NOT want to buy one from Isuzu Commercial!!!!!! They mark up everything 300% over retail & all their parts have Isuzu part numbers that don't cross reference.

Sorry for the Isuzu rant, I maintained a Fleet of them once.....It was a nightmare except for the GM V8 & GM Trans.....I gained ALOT of 4L80E experience/knowledge that I otherwise wouldn't have.

[portell]

Nice, wow, I would have never looked at it being a fleet Isuzu combo. The combo has crazy low miles and I was wondering how the found L96 6.0 when they stopped adding them in trucks 2 years ago. Also explains when I didn't find any info on it on here.

I looked under all the trucks at work and was wondering what this came out, lol. I even looked under the 15 pax vans.

I wont mind keeping the brake if I can find the flange and can find a way for it to fit under the truck.

Slowly prepping the truck for a test fit at the moment, couldnt sit still at work today. Already got the old engine out and just finished pulling the front end of the truck off.



I am putting the combo in my 78 C10, bagged great truck with exception of the old 350

[clinebarger]

Originally Posted by portell

I wont mind keeping the brake if I can find the flange and can find a way for it to fit under the truck.

Well your going to have to mod the trans tunnel anyway too get your Drive Shaft angles right with a slammed Truck anyway, 6L80/6L90 are very TALL units & the PB cable mount being on top makes them even taller.

The only reasons Isuzu does that is......
The same PB Cable for different wheel base trucks.
The rear drums have Dual Wheel Cylinders (Top & Bottom), So there is no anchor available to use a PB.
A tans/DS mounted PB holds better than 2 wheel mounted PB's.

I wouldn't personally mess with it.....But it's not my truck.

On another note, I hope you got the ECM also, Isuzu NPR-HD/W4500 Workhorse have one of the hottest factory tunes, Not that a custom tune couldn't do better. But if your doing mail order just to make it run....The stock tune is pretty good.

[portell]

Thanks a ton, I already had a ton of work to get the truck to drive right before, fortunately I had a 2 piece driveshaft a slip already built in. Once I verify the Flange yoke, Ill find out how much I need to cut out of the driveshaft.

Also I still have the factory tune, I noticed the torque rating the big trucks have.

Got a ton of work done on the truck, did a test fit last night, needed to do some grinding, but the 6l90 does fit, barely. Today I had great weather, so I got the engine and trans mounted up and the front end reinstalled.

[aggie91]

More great info on these LS engines and swaps.

I would see it you could make it work. Just modify the cab floor to make it all fit!

[Rich84]

I also have a 6.0 out of an Isuzu. It's a 4l80 with the parking brake. I used the transmission in my work Van. I had to swap out the tail shaft with the one from the van. I do remember being concerned because the shaft wasn't fully splined. The van driveshaft has the slip built into it and the bolt on yoke worked.

I wonder if it's worth trying to use the parking brake in the future with a rear disc brake swap.