Powertrain: How high is too high? (1 Viewer)

[h82crash]

In fact, mine is, unless I modify the transmission cover. Mocking up the swap. Right now, the only thing below the frame is the transfer case drop.

So, really how low is OK? If the transmission is below the frame rails 1 to 1.5 inches, am I good?

Oh, it's not going to be a crawler.

 

[Vossie]

Similar boat as you. My whole drive train is up high. In my own research it should be fine, only issue is drive shaft angles.

 

[matzell]

I think you need to concern yourself with "belly" height rather than tucking up to the frame. If you are on 40's with 25" belly you are going to be really tall. really 16-18 belly is really good for most stuff depending on wheelbase. The longer the wheelbase the higher the belly needs to be due to breakover angles. Most people want the t-case flush with the frame. They end up with poor driveline angles and never get a scratch on the belly skidplate. If you are going to get into rocks or worried about the belly, build a strong skid plate.

 

[A10Driver]

What matzel said, fj40's are short, too high and u will be fighting drive line vibrations

 

[h82crash]

After looking at some other build photos I dropped the front about 2 inches and the t-case down a little more than an inch. Transmission looks to be barely below the frame rails now. But everything looks way better.

 

[peesalot]

FWIW, I was gonna say cut those front motor mounts in half and thats just about where my ls in my 40 sits, the bottom of tcase is just a bit better than your pic.

 

[h82crash]

It's down but now the front driveshaft is closer to the oil pan. This photo is misleading. A vertical plane, if the shaft was moved straight up, the driveshaft tube is only 1/2 inch clearance from the pan. I'm getting a long spline shaft which should put the end of the DS tube at the rear of the engine where it is further away.

 

[peesalot]

Is that front dline pic at full bump ? I wouldn't worry about it, I have a tight fitting pan skid and the front dline comes right up to it when fully stuffed passenger side, it shears the zerk off the dline tube if it rolls a bit at full stuff passenger side but thats a horizontal dline and the suspension doesn't let it come up that far unless really hammered on the passenger side bump. The steering shaft on the header, use a camaro manifold if it bugs you.

 

[h82crash]

Is that front dline pic at full bump ? I wouldn't worry about it, I have a tight fitting pan skid and the front dline comes right up to it when fully stuffed passenger side, it shears the zerk off the dline tube if it rolls a bit at full stuff passenger side but thats a horizontal dline and the suspension doesn't let it come up that far unless really hammered on the passenger side bump. The steering shaft on the header, use a camaro manifold if it bugs you.

No, it's about ride height. I haven't welded the mounts yet, drivetrain sitting on supports. The end of the tube is about 2.5" below the pan. The new DS should move that back 5 or 6 inches and get it away from the pan. Then just the smaller diameter splined section will be next to the pan and give me more clearance. I'm ok with the steering shaft, and I can get it further away by lengthening the column shaft exiting the firewall. I guess I could notch the corner of the pan, also. But I think the new DS will make me more comfortable. Once I get it all hanging in the frame, I'll articulate the passenger side with a jack and see what happens.

 

[peesalot]

Just hold the driveline straight out from tcase until its an 1/8 or 1/4 inch away from pan, I bet the front diff flange can't possibly achieve that and if it can place your bump accordingly.