Advice Needed: LS V8 & 4L60e & 4 sp Tcase swap into 40 series (1 Viewer)

[gpfj40]

I’m looking for some advice on engine placement from those who have done this swap before. After mocking the drive train in place I’m having trouble finding the best compromise that will lead to overcoming driveline angles and front drive shaft/trans pan clearance issues. These pics are how I’m thinking of proceeding. The front of the engine is shifted 1” to DS, the t case is shifted 1” to the PS. This is helping minimize front drive shaft interference as I hope to use a 1 piece front shaft. The motor and Tcase are as high and as far back as I can place them and they are sitting about 5 deg up sloping to the front. I’ve read as much as I can find on clearancing a 4L60e.

The rear drive shaft angles are ok but not great like this, my stretched wb is making this ok, although I will likely end up with a CV and adjusting the pinion angle if I go as planned. There is more background on the rest of my project in my build thread, the link is in my sig. The short version is: FJ43 with 80 series axles and front coils/radius arms.

Questions:
Is the twisted drivetrain going to cause me some sort of problems I’m not considering?

Should I give up on a 1 piece front driveshaft and start planning for a 2 piece? If so does anyone have any pics they would share of a 2 piece set up?

Am I on the right track by mounting the drivetrain as high as I have mocked it up?

 

[shawnfj40]

Downey is a really good resource for this info. #1 I know that twisted will result in problems and I have no idea why you have shifted everything up so high. #2 what is a "one piece drive shaft" vs. a two piece one? Each shaft has to have a slip yoke.

 

[SuperBuickGuy]

driveshaft angles - the best thing you can do is move the engine as close to the radiator as possible, and lower the transfer case.

I'm not sure, either, why you'd use a driveshaft with a carrier bearing - what's in the way that you need to avoid? On mine, I've been considering a 2 piece shaft (or 3 piece, to be technically accurate), but I'm doing things a bit differently to avoid the weight and complexity of a carrier bearing driveshaft. I went old-school with mine, so the pan issue you're likely dealing with isn't an issue.

 

[gpfj40]

The twisted placement was to minimize interference between the front driveshaft and the trans pan. The reference I make to a 2 piece DS is a shaft that has a carrier pillow block bearing and an extra joint, I was thinking this could help me avoid the trans pan and bring my front pinion angle equal to the front shaft, but that will likely add lots of vibrations to the set up.

I will straighten out the drivetrain, move it as far to the DS as reasonable, move the engine down and forward about 1” and see how that looks. Perhaps my solution lies in a small flag and U joint for the Tcase and a 1.5 or 2” driveshaft.

Thanks for the input.

 

[SuperBuickGuy]

just an FYI, but not really a reasonably priced one.

4L60e from the Hummer H3 have a notch in the transmission oil pan and a corresponding valve body that gives you extra room (the transmission from the rail up is the same as all other 4L60e).... as the cost of a multi-piece driveshaft isn't cheap either - perhaps that option would save you?

 

[Mace]

2 piece driveshafts can be very useful to get items out of the way. Vibrations are typically not that horrible as long as the shaft is balanced. And honestly, how often do you plan to go 60 on the pavement?

Making the Driveshaft that small reduces the strength significantly. There is a reason bigger trucks have those massive driveshafts.

I would do a carrier bearing driveshaft before I'd do a 1.5" diameter driveshaft. One nice thing is that you can still use a stock rear Toyota driveshaft (many trucks used a 2 piece rear stock) for the front axle. Just replace the carrier bearing housing with one of these http://www.hendrixmotorsports.com/id7.html make the lengths fit well, and call it good.

Square the motor up (side to side) and run a 2 piece front. Your rear Driveshaft angles will appreciate it.

 

[Jnkpile]

Are you able to compress the pass suspension to the bump stop to see exactly how much clearance you will require? You can definitely downsize your DS diameter but you'll have to increase the wall thickness to compensate. Your DS shop might have a hard time balancing it if it's too long...

 

[mano002]

How stock do you need to keep the body looking? I'd start with a rear spring flip to get a couple inches of wheelbase.

 

[gpfj40]

I’ve had another look at this. I moved the drivetrain forward a couple inches and straightened it out so it is offset 1” front and rear to the DS based everyones advice. My exhaust builder kit arrived to day from summit so I was able to use a piece of 2.5” pipe to mock up the front drive shaft and I think I can avoid a 2 piece shaft if I can find a u joint or CV (DC) 2.5” or less in diameter. It all of my research I have not found any measurements on toyota flange style CV joints, can any one help with that? Lots of reference to mini truck shafts but no actual measurements.

How stock do you need to keep the body looking? I'd start with a rear spring flip to get a couple inches of wheelbase.

I’ve already stretched the WB 10” to a 43 so I think my rear shaft is ok.

Are you able to compress the pass suspension to the bump stop to see exactly how much clearance you will require? You can definitely downsize your DS diameter but you'll have to increase the wall thickness to compensate. Your DS shop might have a hard time balancing it if it's too long...

My plan is to temp weld the mounts in place, then put the front end to full stuff, then mock the front drive shaft in place and see where I’m at. I’m thinking i could add 1-2” to the front bump stops if needed. At this time I’ll plan out my exhaust crossover.

Square the motor up (side to side) and run a 2 piece front. Your rear Driveshaft angles will appreciate it.

I’m keeping the 2 piece shaft as plan B and I will strive to keep the driveline square.

driveshaft angles - the best thing you can do is move the engine as close to the radiator as possible, and lower the transfer case.

I'm not sure, either, why you'd use a driveshaft with a carrier bearing - what's in the way that you need to avoid? On mine, I've been considering a 2 piece shaft (or 3 piece, to be technically accurate), but I'm doing things a bit differently to avoid the weight and complexity of a carrier bearing driveshaft. I went old-school with mine, so the pan issue you're likely dealing with isn't an issue.

Followed your advise on moving it forward, and dropped the Tcase and inch or so.



Thanks for the input, if anyone can give me an actual diameter from a CV (DC) joint that is on the smaller side I’d appreciate it. I can always buy a new blank Tcase output flange to make any flange style CV joint work.

 

[Mace]

Why not just use a conventional U joint instead of a CV? That'll save a considerable amount of area.

Toyota Mini trucks use a nice, compact U joint that is very strong.


BTW, a 2.5" U joint gets you down to a 1210 ish series U joint. That would be an awesome fuse in your drivetrain. They are very weak...

Toyota conventional U joints are about 3.25" wide. CV's are closer to 4" by the time you get the ball mass.

 

[SuperBuickGuy]

Vortec - he's talking LS motor, not gen 1 small block... though the LS motors say "Vortec" on the top, which adds to the confusion...

 

[Mace]

The transmission setup is very different. Auto oil pans tend to cause drama with the front tcase output.

 

[bomb69tech]

I have a 5.3 with a 4l60e and am running an Orion t/c. My drive train is roughly 1" offset to the driver side. I am running the toy flanges on a standard drive shaft. It does rub a bit on the trans but only enough to take the paint off the drive shaft. At full compression it also hits the crossover pipe just enough to put a small dent in it. Have not had any other issues. A 2 piece is not a horrible idea. I may go to it when I swap axles eventually. How often will anyone go fast enough with the hubs locked or t/c in 4wd.

 

[bomb69tech]

Chicago on here also has the 5.3. He has a pretty detailed build thread. You might be able to see some of his solutions.

 

[gpfj40]

I have a 5.3 with a 4l60e and am running an Orion t/c. My drive train is roughly 1" offset to the driver side. I am running the toy flanges on a standard drive shaft. It does rub a bit on the trans but only enough to take the paint off the drive shaft. At full compression it also hits the crossover pipe just enough to put a small dent in it. Have not had any other issues. A 2 piece is not a horrible idea. I may go to it when I swap axles eventually. How often will anyone go fast enough with the hubs locked or t/c in 4wd.

bomb69tech,
Thanks!! This is the sort of thing I’m real interested to hear about and see. Is there a chance you could post a pic or to of your engine compartment (manifolds/mounts) and the underside (t case/trans/front DS/crossover pipe)? I’ll see if I can find the thread you mentioned.

 

[gpfj40]

Any opinions on this manifold to steering shaft clearance? Is it going to cook my steering shaft u joint?

 

[Mace]

If you're concerned, put a heat shield on it.

 

[gpfj40]

I suppose I should of asked: should I be concerned about this clearance? I do have a couple of solutions in mind such as a heat shield, exhaust wrap, different headers or move the steering shaft. What I don’t know is if I should be concerned, I’m looking for feedback from others who have experience with similar situations.

 

[Mace]

how far away is it? 1/2" or so?
If it's easy to relocate the joint, I would do that just because.

 

[sadam_husain]

yeah I'd be a bit concerned about any engine movement fowling on the universal joint and interfering with the steering it looks pretty close in your picture