gtgt_bangbang
New member
setting differential PRE LOAD ( thrust washer / spacer ).
Manual instruction unclear. Please offerer any advice to question below?
~~~
To summarize what I've read, setting the backlash with differential spacer washers ( ie NOT changing input pinion) method is;
1) place a washer between bearing and axle house on the backside of ring gear (ideally the one that came OUT, if you know it, mine was a .116" or in toyotese 2.94)
check for proper ballpark of backlash, spec .005 to .007".
The diff will be loose of course ( missing teeth-side spacer), and bearing caps NOT installed. Tilt axle if possible to seat diff against backside washer.
2) insert tooth-side spacer(s) selected for ZERO CLEARANCE to other side (called "teeth side", but again between diff & case.) Zero clearance spacer step lets you check backlash again without too much trouble to dismantle for adjusts. Turning pinion, slipping in thin spacers first, tapping and a little shakem baby got the (tight-ish) zero clearance pack in.
Verify back space again 005~007.
There is a special spacer tool, a hooked lever that lets you tug out washers thru the gap in the axle house. Seems very simple tool, but have not seen one around, looks like you could easily make one from grinding down a gear puller arm to fit.
3) Adjusting backlash if necessary;
INCREASE BACKSIDE WASHER THICKNESS to REDUCE LASH (mesh gears closer),
REDUCE BACKSIDE WASHER to INCREASE LASH (gears further apart).
By the way, manual says .0012" washer change should change backlash 0.0008"
4) remove ZERO CLEARANCE washer and replace it with a .002~.003" THICKER washer, to set "pre load", or basically to cram that diff in there, fairly damn tight. This washer will take some convincing to go in, of course. Elsewhere advice says its very hard to OVER pre-load the bearings, so no need to be too shy about coaxing in a pre-load washer of maybe 001 or 002 TOO thick if thats what you have, depends on how willing & adept you are to hammer it in with out damaging any thing.
~~~~~~~
Now this all seems logical HOWEVER the (translated) toyota manual is unclear;
To me, it makes sense that there is a total spacer thickness (backside plus tooth side washers, mine was about .231" , or = .115 + .116" ), so if you find yourself INCREASING one washer, to adjust backlash, the other washer should DECREASE the same amount, to maintain the same preload.
This is what I am doing - going to a 118 (back) /113 (tooth) washer pair.
The manual however says a confusing "if backlash is not w/in spec, adjust by increasing or decreasing the washers on both sides by equal amount", which seems to say " throw preload to the wind", illogically says if you increase the backside, increase the tooth side too.
Again, I think what they mean to say (before the japanglish translator)
is IF INCREASING ONE WASHER, DECREASE OTHER WASHER BY SAME AMOUNT.
Am I right ? Any diff guys want to chime in ?
Manual instruction unclear. Please offerer any advice to question below?
~~~
To summarize what I've read, setting the backlash with differential spacer washers ( ie NOT changing input pinion) method is;
1) place a washer between bearing and axle house on the backside of ring gear (ideally the one that came OUT, if you know it, mine was a .116" or in toyotese 2.94)
check for proper ballpark of backlash, spec .005 to .007".
The diff will be loose of course ( missing teeth-side spacer), and bearing caps NOT installed. Tilt axle if possible to seat diff against backside washer.
2) insert tooth-side spacer(s) selected for ZERO CLEARANCE to other side (called "teeth side", but again between diff & case.) Zero clearance spacer step lets you check backlash again without too much trouble to dismantle for adjusts. Turning pinion, slipping in thin spacers first, tapping and a little shakem baby got the (tight-ish) zero clearance pack in.
Verify back space again 005~007.
There is a special spacer tool, a hooked lever that lets you tug out washers thru the gap in the axle house. Seems very simple tool, but have not seen one around, looks like you could easily make one from grinding down a gear puller arm to fit.
3) Adjusting backlash if necessary;
INCREASE BACKSIDE WASHER THICKNESS to REDUCE LASH (mesh gears closer),
REDUCE BACKSIDE WASHER to INCREASE LASH (gears further apart).
By the way, manual says .0012" washer change should change backlash 0.0008"
4) remove ZERO CLEARANCE washer and replace it with a .002~.003" THICKER washer, to set "pre load", or basically to cram that diff in there, fairly damn tight. This washer will take some convincing to go in, of course. Elsewhere advice says its very hard to OVER pre-load the bearings, so no need to be too shy about coaxing in a pre-load washer of maybe 001 or 002 TOO thick if thats what you have, depends on how willing & adept you are to hammer it in with out damaging any thing.
~~~~~~~
Now this all seems logical HOWEVER the (translated) toyota manual is unclear;
To me, it makes sense that there is a total spacer thickness (backside plus tooth side washers, mine was about .231" , or = .115 + .116" ), so if you find yourself INCREASING one washer, to adjust backlash, the other washer should DECREASE the same amount, to maintain the same preload.
This is what I am doing - going to a 118 (back) /113 (tooth) washer pair.
The manual however says a confusing "if backlash is not w/in spec, adjust by increasing or decreasing the washers on both sides by equal amount", which seems to say " throw preload to the wind", illogically says if you increase the backside, increase the tooth side too.
Again, I think what they mean to say (before the japanglish translator)
is IF INCREASING ONE WASHER, DECREASE OTHER WASHER BY SAME AMOUNT.
Am I right ? Any diff guys want to chime in ?
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