I wasn't getting a lot of response in the General Tech forum so I am posting it in the 60 section. Any help, especially from someone who has done this before, is appreciated.
Measuring backlash with the 3rd member in the axle (1 Viewer)
- Thread starter chbrow10
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OTRAAM has a bunch of videos on diff rebuilds.
- Thread starter
- #3
I agree. They all seem to have the 3rd member removed from the axle and I'm trying to see if backlash can be measured with the 3rd member still installed in the truck with the half shafts in the carrier. Just trying to diagnose without tearing everything apart.
You could turn the axles with the drive shaft locked and see how much play there is. This will also measure the wear in the splines, not sure how significant that would be. On my 80 series FF rear, there is minimal play.
Edit: or rather, turn the driveshaft with the axles locked (i.e. wheels on ground)
Edit: or rather, turn the driveshaft with the axles locked (i.e. wheels on ground)
I just checked my 4runner axle and the prop shaft moves maybe 5 degrees with the wheels on the ground. I think it's a good axle. It is semi float.
You cant accurately measure backlash with the diff in the truck. Any play from the bearings through the axle shafts will amplify the measurement and make it inherently inaccurate.
You can get a feel for how much backlash it has while in the truck, but it will always feel like "a lot" especially to untrained hands.
You can get a feel for how much backlash it has while in the truck, but it will always feel like "a lot" especially to untrained hands.
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Agreed. Which diff are you curious about, the front or the rear? The rear will have play from the axle shafts, spider gears, cross pin, even if you lock the parking brake. The front has all that plus the birfs, shafts, hubs, etc. There is enough tolerance in the front end that it can be difficult to determine what ratio differential the front has, let alone something like backlash measured in thousandth of an inch increments
- Thread starter
- #8
the rear
- Thread starter
- #10
I don't know. it is 12-13 thou to a FSM spec of 6-8. so 4 thou out of tolerance. 34 year old truck. Is that ok? That's with the axles removed.
How are you measuring, with a dial indicator on the ring gear, shifting the ring gear back and forth until it touches the pinion on coast/drive?
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- #12
yes.
Reference for others:
Yes, that's a decent amount of slop. Adjust the backlash, not a big deal to do now that you have the axle shafts out.
Yes, that's a decent amount of slop. Adjust the backlash, not a big deal to do now that you have the axle shafts out.
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- #14
Tooth pattern isn’t terrible. I’m inclined to leave it
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- #15
It's your diff.
When setting up a diff, you have to find the happy medium between preload, backlash, and pattern. If any are off, it'll reduce longevity.
If you know enough to read patterning compound on the ring gear, then you know what I'm talking about.
When setting up a diff, you have to find the happy medium between preload, backlash, and pattern. If any are off, it'll reduce longevity.
If you know enough to read patterning compound on the ring gear, then you know what I'm talking about.
- Thread starter
- #17
I do. I’m planning on putting a locker in here within two years, so this is just being a procrastinator.
