Gear change report D36
01-23-2006, 11:58 PM
#1
Burning Brakes
Thread Starter
Gear change report D36
Just so we don't waste any Mb's, yes the D44 is stronger, yes the D36 is not as strong, yes the d36 with gears and good slicks will crack.
Now to the info. First off (you can read from my posts) I just don't quit. It was suggested by my transmission guy(s), clutch guy, anyone here of the forum, to upgrade the gears on the car.
I had the 2.59 rear ratio, running through a ZF-6 (yes a conversion), mini-ram 383 224/230 near solid lifter cam. The sub-standard trannies and clutches were not keeping up.
I choose the 3.73 performance strange gear set. (Hey made in the USA always gets a look from me).
As far as instructions and help it's just not out there. There is no such thing as the perfect pattern. Of course this may have been due to the performance edition of the gears rather than normal.
What made this worse was that I was trying to do so while recovering from a knee surgery (DRUGS).
The final tally was 55 different settings of pinion depth and ring offset. As an engineer, I figured since the docuementation out there wasn't helpful I just make changes and record the results. This way (Called the brute force method) help me to understand how the settings interacted.
Some key notes. First, stock pinions are marked +1, +2, -1, -5, and so on. This is so when you change to a new gear set, you have a starting point for the pinion gear....My pinion was marked 2.548" pinion...WTF! As I found out the (I could still be wrong) the stock pinion depth for a D36 is 2.468"...is this thing really .100+" off.
The second thing is that there are two sets of pinion setting shims. One is a .028" thick spacer between the pinion gear and the bearing. The second set of shims lay behind/underneath the pinion bearing race. This little bit of info could have helped when determining pinion depth. But it didn't really matter because of above ph.
The third thing is that you really should get a limited slip rebuild kit (clutch packs) when you buy the install kit. I really regret not doing this refresh since I was there man...I was there. It's abouta 125 bucks; and for us resto-mod 100K+ mile cars, it's really should be part of the job.
The fourth thing is you absolutely need a hydraulic press wide enough to fit the carrier. The larger of the two at harbour frieght isn't wide enough. I had to go to a steel yard a procure two I beam 18" sections. Even with making the "practice bearings", you'll need to pull/press your final bearings at least once. (I needed twice).
(Fifth) Speaking of bearings, the strange and ratech use timken carrier bearings. But the bearings themselves are not width control. Meaning that you may need more or less shims from your practice bearings to your final bearings. My difference 4 thou on each bearing. Take time to measure each bearing hieght, and use the same bearings on their side of the carrier. By switching the races alone, I could adjust the backlash by 1 thou.
Sixth, tools. Oddly, the the dail indicator and magnetic base from barbour frieght are perfect for this. The stand do-dad screws right into the D36 case (metric). I also used a sears breaker bar...which for measuring pinion drag was perfect. At 16" inchs, the load in ounces becones lb-in...16 ounces in a pound.
seventh, since I'm not a fan of power/air tools I had to find a way to hold the pinion yolk while tightening the nut to 190+ lb-ft. I used the biggest MF plumber's wrench from lowes to grab the yolk while tightening down the nut. Using the breaker bar (and the ghetto extendo 1" dia 48" pipe breaker) to tighten the nut. Leverage...gotta love it.
eigth the don't dos before you do. The directions say don't install the pinion seal. Actually, don't install seals nor the side yolk bearings. They'll just get in the way when you're doing your cleanings.
Ninth, don't kid yourself. Everytime you set up the gears for pattern and backlash, the setup up must be tight. Use all carrir shims, and tighten the pinion down to 25 lb-in of drag. It makes a difference. Had I known this... finally, rotate the carrier around a couple of revs. I always seem to find an extra 2 to 5 thou in backlash. This is probably from dust on the gears.
My results. I set the pattern up for the drive side with a backlash of .00525ish". Though the directions said for .006" to .008" for performance uses. I had to remove the pinion .028" spacer...so the strange gear should've been marked +6. I did the normal but abbreviated break in. 5 miles...30 minute cool...50 miles...2 hour cool...1300 miles....it's still cooling in NM. No ticking or cracking while on the power. I do have a S/C type whine on decel (coast) that decreased as miles where added to the machine.
I had the case and bearings cyro treated. Some my ask why not the ring and pinion. My answer is that if I have to worry about the pinion or ring cracking, then the ****-poor d36 case has alreadt exploded into little bits. My new cryo guy has a REM process (cyro and surface treatment) that has proven to be a stronger and more efficient (less heat) for the gears. When I step up to the D44, this will definitely be one of my to do's.
This concludes my briefing are there any questions?
Now to the info. First off (you can read from my posts) I just don't quit. It was suggested by my transmission guy(s), clutch guy, anyone here of the forum, to upgrade the gears on the car.
I had the 2.59 rear ratio, running through a ZF-6 (yes a conversion), mini-ram 383 224/230 near solid lifter cam. The sub-standard trannies and clutches were not keeping up.
I choose the 3.73 performance strange gear set. (Hey made in the USA always gets a look from me).
As far as instructions and help it's just not out there. There is no such thing as the perfect pattern. Of course this may have been due to the performance edition of the gears rather than normal.
What made this worse was that I was trying to do so while recovering from a knee surgery (DRUGS).
The final tally was 55 different settings of pinion depth and ring offset. As an engineer, I figured since the docuementation out there wasn't helpful I just make changes and record the results. This way (Called the brute force method) help me to understand how the settings interacted.
Some key notes. First, stock pinions are marked +1, +2, -1, -5, and so on. This is so when you change to a new gear set, you have a starting point for the pinion gear....My pinion was marked 2.548" pinion...WTF! As I found out the (I could still be wrong) the stock pinion depth for a D36 is 2.468"...is this thing really .100+" off.
The second thing is that there are two sets of pinion setting shims. One is a .028" thick spacer between the pinion gear and the bearing. The second set of shims lay behind/underneath the pinion bearing race. This little bit of info could have helped when determining pinion depth. But it didn't really matter because of above ph.
The third thing is that you really should get a limited slip rebuild kit (clutch packs) when you buy the install kit. I really regret not doing this refresh since I was there man...I was there. It's abouta 125 bucks; and for us resto-mod 100K+ mile cars, it's really should be part of the job.
The fourth thing is you absolutely need a hydraulic press wide enough to fit the carrier. The larger of the two at harbour frieght isn't wide enough. I had to go to a steel yard a procure two I beam 18" sections. Even with making the "practice bearings", you'll need to pull/press your final bearings at least once. (I needed twice).
(Fifth) Speaking of bearings, the strange and ratech use timken carrier bearings. But the bearings themselves are not width control. Meaning that you may need more or less shims from your practice bearings to your final bearings. My difference 4 thou on each bearing. Take time to measure each bearing hieght, and use the same bearings on their side of the carrier. By switching the races alone, I could adjust the backlash by 1 thou.
Sixth, tools. Oddly, the the dail indicator and magnetic base from barbour frieght are perfect for this. The stand do-dad screws right into the D36 case (metric). I also used a sears breaker bar...which for measuring pinion drag was perfect. At 16" inchs, the load in ounces becones lb-in...16 ounces in a pound.
seventh, since I'm not a fan of power/air tools I had to find a way to hold the pinion yolk while tightening the nut to 190+ lb-ft. I used the biggest MF plumber's wrench from lowes to grab the yolk while tightening down the nut. Using the breaker bar (and the ghetto extendo 1" dia 48" pipe breaker) to tighten the nut. Leverage...gotta love it.
eigth the don't dos before you do. The directions say don't install the pinion seal. Actually, don't install seals nor the side yolk bearings. They'll just get in the way when you're doing your cleanings.
Ninth, don't kid yourself. Everytime you set up the gears for pattern and backlash, the setup up must be tight. Use all carrir shims, and tighten the pinion down to 25 lb-in of drag. It makes a difference. Had I known this... finally, rotate the carrier around a couple of revs. I always seem to find an extra 2 to 5 thou in backlash. This is probably from dust on the gears.
My results. I set the pattern up for the drive side with a backlash of .00525ish". Though the directions said for .006" to .008" for performance uses. I had to remove the pinion .028" spacer...so the strange gear should've been marked +6. I did the normal but abbreviated break in. 5 miles...30 minute cool...50 miles...2 hour cool...1300 miles....it's still cooling in NM. No ticking or cracking while on the power. I do have a S/C type whine on decel (coast) that decreased as miles where added to the machine.
I had the case and bearings cyro treated. Some my ask why not the ring and pinion. My answer is that if I have to worry about the pinion or ring cracking, then the ****-poor d36 case has alreadt exploded into little bits. My new cryo guy has a REM process (cyro and surface treatment) that has proven to be a stronger and more efficient (less heat) for the gears. When I step up to the D44, this will definitely be one of my to do's.
This concludes my briefing are there any questions?
01-24-2006, 06:52 PM
#2
Le Mans Master
Wow! Very informative... definitely a "from the trenches" description. Anyway, I thought it was a good read. Something that I have always kinda wondered about: DIY changing gears.
Here's a bump.
Here's a bump.
