Hello Forum,
First, I have read the threads, seen ZUKs site, watched 2 youtube video's numerous times (part 1 and 2 ARB Fj40 Install, Tacoma ring and pinion install professional guy provides tips), bought a diff rebuild book.
I am attempting, 1st time, both front and back 4.88 Sierra Gears with Airlockers. I have a few questions for those that have related experience.
It's my understanding correct about backlash? Backlash is set by moving the ring toward or away from the pinion via the diff adjust nuts. Move the ring towards the pinion the space between the pinion teeth and ring teeth is less therefore the blacklash is less. Move the ring away from the pinion and the backless is more.
Once the backlash is set (further assume the pinion depth is also set and so is the pinion pre-load) would I have to tighten both diff adjust nuts in uniform to further load the carrier bearings or can i just assume no further adjustments to the diff adjust nuts? From what I read, on this forum, the pre-load should go up by 10 ft lbs when the locker/diff is installed and setup correctly.
Pinion depth is set by putting shims under the pinion race. I would rather put shims between the pinion and pinion bearing as I think it is more of a f-ing pain to beat the racer in and out to add and remove shims than to use a puller on the bearing to add shims under the bearing. My experience with this process is once I have to replace the shims they are ruined. There is not enough space on the back of the race to not beat on part of the shims with a drift to pop the racer out. Therefore once I pop the racer out to adjust the shims the shims have dents in them from the drift. Is it OK to reuse the shims or are they garbage now?
I cannot understand my contact pattern. I am not getting a good readable patter/well they don't look as readable as what is see on the youtube videos. What are peoples thoughts on the pattern? I loaded up almost all my shims on this go: 2 - 8mm, 3 - 5mm, 2 - 3 mm. I think the pattern shows the pinion is too shallow however considering all the shims I figured it would be to deep. Shallow, as I interpret it, means the pinion is not close enough to the ring gear and needs more shims. Deep, as I interpret it, means the pinion is over shimmed.
Last 2 piece of information. This is a Fj80 3rd member but I assume this really makes no difference as rear 3rd members on all LC are interchangeable. right? The front pinion bearing I am not installing while I try to set up the blacklash and pinion depth. The reason for this is, its a pain to press on and off the front bearing while I try to get this all setup. I just keep the 3rd member in a fixture, ass end down, and put the flange on with the flange nut. However maybe this is a bad idea and part of the reason why I don't get a great contact pattern because the pinion would be more stable with both bearings seated. Thoughts?
Attached is was most recent pattern. "First" means it was the first turn, back and forward. "Second" I added more gear paint back and did a second turn, back and forward.
Backlash Check: - looks right to me at .006
First, I have read the threads, seen ZUKs site, watched 2 youtube video's numerous times (part 1 and 2 ARB Fj40 Install, Tacoma ring and pinion install professional guy provides tips), bought a diff rebuild book.
I am attempting, 1st time, both front and back 4.88 Sierra Gears with Airlockers. I have a few questions for those that have related experience.
It's my understanding correct about backlash? Backlash is set by moving the ring toward or away from the pinion via the diff adjust nuts. Move the ring towards the pinion the space between the pinion teeth and ring teeth is less therefore the blacklash is less. Move the ring away from the pinion and the backless is more.
Once the backlash is set (further assume the pinion depth is also set and so is the pinion pre-load) would I have to tighten both diff adjust nuts in uniform to further load the carrier bearings or can i just assume no further adjustments to the diff adjust nuts? From what I read, on this forum, the pre-load should go up by 10 ft lbs when the locker/diff is installed and setup correctly.
Pinion depth is set by putting shims under the pinion race. I would rather put shims between the pinion and pinion bearing as I think it is more of a f-ing pain to beat the racer in and out to add and remove shims than to use a puller on the bearing to add shims under the bearing. My experience with this process is once I have to replace the shims they are ruined. There is not enough space on the back of the race to not beat on part of the shims with a drift to pop the racer out. Therefore once I pop the racer out to adjust the shims the shims have dents in them from the drift. Is it OK to reuse the shims or are they garbage now?
I cannot understand my contact pattern. I am not getting a good readable patter/well they don't look as readable as what is see on the youtube videos. What are peoples thoughts on the pattern? I loaded up almost all my shims on this go: 2 - 8mm, 3 - 5mm, 2 - 3 mm. I think the pattern shows the pinion is too shallow however considering all the shims I figured it would be to deep. Shallow, as I interpret it, means the pinion is not close enough to the ring gear and needs more shims. Deep, as I interpret it, means the pinion is over shimmed.
Last 2 piece of information. This is a Fj80 3rd member but I assume this really makes no difference as rear 3rd members on all LC are interchangeable. right? The front pinion bearing I am not installing while I try to set up the blacklash and pinion depth. The reason for this is, its a pain to press on and off the front bearing while I try to get this all setup. I just keep the 3rd member in a fixture, ass end down, and put the flange on with the flange nut. However maybe this is a bad idea and part of the reason why I don't get a great contact pattern because the pinion would be more stable with both bearings seated. Thoughts?
Attached is was most recent pattern. "First" means it was the first turn, back and forward. "Second" I added more gear paint back and did a second turn, back and forward.
Backlash Check: - looks right to me at .006