▲True▲ only without a DC shaft. You want your pinion to point directly to the t-case with a DC.
Castor/pinion angle question for de-grring (1 Viewer)
- Thread starter hammerheadfistpunch
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▲True▲ only without a DC shaft. You want your pinion to point directly to the t-case with a DC.
Going part time to combat drive line vibrations below 5" of lift is stupid. There are solutions out there.
Probably not gonna happen.
I think @baldilocks pointed out in another thread, the front diff pinion points upward in standard trim and with caster correction in place. Without caster correction, the pinion angle increases, but the drive shaft angle flattens out.
The front pinion and t case flanges will always be out of parallel without modifying the diff housing.
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- #25
Ideally
According to your measurements you have a 3 degree working angle on the front u-joint and 12 degree on the rear, a recipe for vibes. Unfortunately, and I'm sure others will disagree, I believe the caster adjustment is the root of the problem. Toyota did a pretty good job of controlling the pinion angle through suspension travel in regards to drive line working angles but they did it at the expense of poor control of caster change through suspension travel. Its a catch 22, The more you change pinion angle to correct caster angle the more you increase the potential for drive line vibration.
The way I see it, you have 4 choices, 1. Reinstall the factory bushings at the expense of stability at speed(thats the route I chose), 2. Install a DC driveshaft(you're within the ideal pinion angle to make it work but 2 more degrees of positive caster would put you spot on). 3. reinstall the factory bushings and do a cut and turn(could get very expensive as you may need to covert to front steer). 4. Do a part time conversion and not worry about the angles as the driveshaft never spins fast enough for any of it to matter.
The way I see it, you have 4 choices, 1. Reinstall the factory bushings at the expense of stability at speed(thats the route I chose), 2. Install a DC driveshaft(you're within the ideal pinion angle to make it work but 2 more degrees of positive caster would put you spot on). 3. reinstall the factory bushings and do a cut and turn(could get very expensive as you may need to covert to front steer). 4. Do a part time conversion and not worry about the angles as the driveshaft never spins fast enough for any of it to matter.
Whatever, no need to go part time
nice rebuttals, care to expand on it ?
Btw, Toyota went with a "broken back" style front driveline meaning that rather than going for parallel flange angles they are equal but opposite in relation to the driveshaft. Cadillac did something similar in the 60's to minimize the driveshaft hump.
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- #29
I noticed that while I was in there last night. Strange. I'm doing a DC shaft from Tom woods, it's at my house tomorrow. Stoked.
Cut and turn has it's own set of problems.
I did a cut and turn on my hdj81 with a 4" lift and factory bushes, I would not be in a rush to repeat it.
It increases pinion angle, and highly likely causes tie rod interference on radius arms.
I had 4° caster. Handling was exceptional.
Tie rod interference means a high steer conversion, or a modified tie rod set up.
I had a heavy duty tie rod made, using heim joints and drilled out the taper in the steering arms for bolts and spacers to bolt through the heim joints to lift the tire rid and get clearance from the radius arms.
I ran full time 4wd, and the standard shaft. With new uni joints, I had a slight grrr, but it was tolerable.
For a daily driver, I would be maintaining positive caster and predictable handling.
Im at 4° caster (using plates) and yes it handles like a dream but I had the same tie rod arm clearance issue and needed to cut my arms to get the needed clearance for the flex I have.
Having owned several 80 I have not be able to get 100% vibs front drive line out at speed nor have I ever drove one or been in one. YMMV
So you confirmed with obd2 reader and it's actually running that cool?
I just went thru this with mine. Gauge sender was going bad but it would drop to 1/4 then jump back to 1/2. Replaced gauge sender (and ecu sender while I was in there) and it read about 20* too high, swapped to a different brand and it reads a little low but I'm tired of messing with it, at least it's consistent. (And this is the part to advocate OEM parts!)
Also, do you mind posting a pic of your control arms? I'm also grinding mine for 4* caster clearance! I took enough off to drive the streets but I know it's rubbing even on bumpy turns, need to grind more before next off road trip.
I agree the OEM gauge is not a good judge of temp. My gauge has been modded to be more active reflecting small temp changes. The pic was taken raining at 7200' guessing I would estimate temp at 177° - 180° I have run both ScanGauge & Ultragauge and confirmed my 80 just runs cool
, rarely seeing 200° anytime. Picture not so great but I have a good 1/2" of clearance and you can see I still can make tie rod contact when flexed.
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- #35
I agree the OEM gauge is not a good judge of temp. My gauge has been modded to be more active reflecting small temp changes. The pic was taken raining at 7200' guessing I would estimate temp at 177° - 180° I have run both ScanGauge & Ultragauge and confirmed my 80 just runs cool
Picture not so great but I have a good 1/2" of clearance and you can see I still can make tie rod contact when flexed.
View attachment 1544852
Makes me wonder if thats the bang I hear with the sway bar out wheeling hard. It only happens on the passenger side and only at full stroke. hmm.
I doubt you will hear a bang, the contact is not so abrupt. The contact is under flex and more sliding of the tie rod and arms. Who's plates are you running? Also you do not need to remove your sway bar I heard someone makes swaybar disconnects to get you home safely.
My needs are definitely specialSome have special needs also one does not need PT to run solo on a front driveline but it will come in handy if you have front end issues.
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- #38
Plates? Also I know about your sway bar kit cause I'm running it.
What are you using for caster correction and do you know what your caster readings are?
Thanks for your product support.
- Thread starter
- #40
What are you using for caster correction?
Thanks for your product support.
OME bushings the 2.5 offest. I am thinking about getting those adjustable ones to get back a little more caster after the driveshaft comes in. Try and get the correct caster/pinion angle combo. It drives okay right now, a little wandery, but truthfully I think thats more 300k worth of steering gear than castor.
