FJ40 Upgrade: Offset Teraflex High Pinion D60, 14 Bolt Hybrid Rear Axle

[Rock40]

@matzell, here you go. Measuring for the rear driveshaft today

 

[Rock40]

Getting close to having it all in. I’ll need to make new upper links that’ll clear the driveshaft at full passenger bump along with some exhaust work to clear the upper links.

Driveshaft measurements are done

 

[matzell]

@matzell, here you go. Measuring for the rear driveshaft today


View attachment 3882788

Thank you!

 

[Rock40]

Making some progress. About to chuck it in the truck, lift the rear tires and determine how true it’s running. Before the welding gets any further.

And that is 2.5” OD .25” wall tubing. No more bent driveshafts

 

[Rock40]

Hmmmmm. I think….not great.

Open to suggestions. I believe the pinion needs to come down but I can only bring it down maybe 5°-6° total or so.

Driveshaft is FLAT, 1° downwards from the Orion

More or less flat at the Orion yoke

And this is the issue. I believe 1410 joints are good to around 35° of operating angle. I care nothing about wearing out u-joints. I do care about it vibrating at highway speed.

Top of the truss is sitting at 0° here. Pinion is upwards 16° total.

I should add that as the suspension cycles, the angles aren’t going to change much based on the measurements I took. Some, not much. The driveshaft slip is only about 3/16” overall

Anybody have thoughts? I can only rotate the pinion downwards so much before the angles on the coil buckets and shock mounts get totally screwed. Oh if only I had 16” of lift

 

[Ditcherman]

Hmmmmm. I think….not great.

Open to suggestions. I believe the pinion needs to come down but I can only bring it down maybe 5°-6° total or so.

Driveshaft is FLAT, 1° downwards from the Orion


View attachment 3883791


More or less flat at the Orion yoke


View attachment 3883792


And this is the issue. I believe 1410 joints are good to around 35° of operating angle. I care nothing about wearing out u-joints. I do care about it vibrating at highway speed.


View attachment 3883793


Top of the truss is sitting at 0° here. Pinion is upwards 16° total.

I should add that as the suspension cycles, the angles aren’t going to change much based on the measurements I took. Some, not much. The driveshaft slip is only about 3/16” overall


View attachment 3883794


Anybody have thoughts? I can only rotate the pinion downwards so much before the angles on the coil buckets and shock mounts get totally screwed. Oh if only I had 16” of lift

From my reading - not experience - you want equal opposing angles at both ends of the shaft to prevent vibration. So if you could split that 16 into 8 on each end you would have zero vibration, but 16 on one end will not be good.

How hard is it to flatten the pinion and remodel the buckets and shock mounts?
Many would go to great lengths to have virtually no angles, 3/16 slip if packaging allowed at all.

 

[Ditcherman]

Hey how about a double cardon at the pinion end?
Call Tom Woods Custom Drive Shaft Shop | Tom Wood's Custom Drive Shafts - https://4xshaft.com/?gad_source=1&gbraid=0AAAAACiJmHXlxw3CPKW-0q0wj60bor8Q5&gclid=CjwKCAjwwe2_BhBEEiwAM1I7sTxddbhu5p4836goLsx_Yuc2a7f2KyhzKFMLcs5XLo7N58jG241B1xoCAvgQAvD_BwE
Knowledgeable and they care.

 

[Rock40]

From my reading - not experience - you want equal opposing angles at both ends of the shaft to prevent vibration. So if you could split that 16 into 8 on each end you would have zero vibration, but 16 on one end will not be good.

How hard is it to flatten the pinion and remodel the buckets and shock mounts?
Many would go to great lengths to have virtually no angles, 3/16 slip if packaging allowed at all.

Well, cutting that all off and starting from scratch would be no fun. At all. And it’s occurred to me for sure.

I don’t believe I can drop the transfer 8 degrees unfortunately, it’d be hanging WAY down there.

I will call Tom Woods about the CV on the pinion side, was already thinking that way would be easiest, maybe.

I really SHOULD have checked this long ago but I didn’t want to tear the working/driving 40 apart at that point. Hard lesson

 

[matzell]

@matzell, here you go. Measuring for the rear driveshaft today


View attachment 3882788

So a C&C hub is about 3 7/8", so wms with these on an older 14b would be about 64 3/4" which is about the same as the 2nd gen 14b at 65" wms.

 

[matzell]

I would try to measure it again after dropping it to 8 deg. then the angle on the t-case may change to the better? Not sure I would want a double cardian at the pinion, that is a lot of low hanging fruit to catch on rocks.

 

[peesalot]

Roll it down, add to the spring pads for level, redo the shock tabs & maybe the sway tabs, might have to shorten uppers but all that aint that bad. I'd prolly run it first and see what happens then if I hated it I'd make those adjustments.

 

[Rock40]

All good advice from everyone. I did call Tom Woods, talked to Troy in tech for at least 20 minutes which was very helpful. He basically said the same thing, “bring the pinion down and see what happens”. A CV won’t improve anything.

So…. Plan is to drop the pinion, put a few road miles on it and see. I may hit some dirt Saturday, IDK. Still lots to do.

 

[peesalot]

A shout out to Rock40 having a great attitude & mad skills. I'd have lost it.

 

[Rock40]

Made it out today, over in Liberty, WA.

Did I break the rear TeraFlex CRD60? No. It worked great. Did the rear driveshaft come apart? No it did not, and I certainly tried my best

Got it up to 50mph on the hwy, really only a slight vibration in 2nd gear.

Did I destroy the PSC power steering pump on its very first run out? Well yes I did. I’m thinking it doesn’t like bouncing off the rev limiter around 6,500 rpm with an under drive pulley

 

[Rock40]

 

[Rock40]

And this was the end of the PSC pump. It’s hard to tell how steep this is. It is STEEP. With very soft late season snow and mud

 

[Mike Shull]

This thing sounds mean! Sorry to hear about the pump. Hopefully it’s the last one that you have to replace in this. Looks like fun. I can’t wait to get mine out.

 

[Rock40]

This thing sounds mean! Sorry to hear about the pump. Hopefully it’s the last one that you have to replace in this. Looks like fun. I can’t wait to get mine out.

I frankly don’t know WHAT is going on with the steering pumps lately. I ran a PSC for 13 years before it wore out. This one lasted 1/2 a day. Stock one lasted 1/2 a day 6 months ago

I’ll send this one back to PSC. I have to wonder if the PSC under drive pulley I’m running on it is just too much for high rpm hill climbs.

And yes, the 6.0 LS is running well. Makes power REALLY fast with the cam and 11.5:1 compression. Get out there, it makes all the fab and tedium worth it

 

[matzell]

I have burned up many pumps with stock pulleys in my race car. you have to lower the rpms to keep them from burning up. They do not like anything over 6k, the other thing is to make sure you have plenty of fluid and a good return. I pulled the filter out of my reservoir per a tech at PSC. only after running it a bit to make sure the fluid was clean after assy.

Edit: I am runnign PSC P-pumps and have burned them up too. I need to lower my rev limiter

 

[Rock40]

Thx, that’s great info. I’ll remove the filter on my low pressure return line, it’s likely a restriction. And probably go back to a factory pulley. I’ll call PSC next week, get the pump set back and see what they say. I also want to make sure the pump is compatible with the hydroboost. I know it’s good for running the PSC ram but the hydroboost is likely an additional load on it