Pinion Depth
- Thread starter cumins01
- Start date
YoungDiesel27
Never Enough Time
And also we sled pullers are going 25-30mph with approximately 35-45mph wheels speeds depending on motor and gear combos. And that all tries to be brought to a stop by the sled. I'm ok with getting 10+hooks out of a set. If it got to be less than that for me i would be looking for a different solution. I agree with getting away from the 4.88 gear as the 4.56 is stronger if you have enough motor to run it.
Ended up with one from TD Machine in Navada.
Got it setup guys. Thanks for all the input. Used .057 on the pinoin for the depth (old set I took off the total was .078 and when I removed the pinion race in the housing, I had some shims behind it along with putting some between bearing and pinion. Reading the book over and over got way to confusing) Put shims behind race and setup with a tighter rolling torque. Installed carrier and correct shims to get backlash of .001 then added .010 to each side of the carrier so I has to wedge it into the case. Hopes this works this time.
whitneyj
still in pieces
You have to have a high pinion axle to run reverse rotation gears.
That being said, if low pinion D60 gears aren't lasting in the front axle swap for a high pinion front D60. Low pinion in the rear and high pinion in the front has the gears being driven with the most contact area making that the strong side of the gear to put the power to.
OP-good luck with this set of gears. If these failed I'd very seriously try a different brand. Like I said, I've never heard of these gears in any of the axle worlds I play around in (crawling being the most abusive), so they're definitely not top tier.
whitneyj
still in pieces
I don't see any way that the gears can be broken in with a dedicated puller. The axle would have to be swapped under a street truck and then swapped back into the puller.
I don't know much about the puller world other than I don't make enough money for it, but how I see it is in the 1/4 mile the most abuse the drivetrain sees is the launch while on a puller the launch is the easiest and the drivetrain only sees more torque the further down the track it goes with a violent release of torque at the finish (opposite of a drag launch). I could be wrong but that's how it makes sense in my head. My very under coffee-ed, fuzzy head.
Supershafts
We race, so You win
Sure they do just like drag cars with filled blocks. Have you even been at the track and watched a drag car that is usually very fast make a few slow passes.
Break-in are 2 heat cycles, atleast thats what we like to see, 2 heat cycles.
Driving around the pits is what they do to get heat into the diff.... not good to hammer everything cold, which is another problem
lapping, run in
No drag racers aren't dragging weight exactly but, they are instantly putting a hard hit to the gear at rest, which is more violent than pulling.
Pulling see's more weight as it gets further down track, where the weight either stops it or they get off it.
Increasing load isn't as violent as leaving from rest.
However setting up gears in bind is not doing anything for longevity or making them live longer.
Supershafts
We race, so You win
Now don't take this as im attacking you but....this is the problem with building diffs.. and i see professional shops make the same mistakes also...
This is also the biggest reason for failures....
Im going to point out what he said he did and lets see if anyone who claims to know how to build diffs can add whats missing... Again im not doing this to goof on anyone.
He set the pin depth with a .057 shim (which is the 1st step to get correct)
He gave it a tighter rolling torque (im assuming this is pinion preload)
He then set BL to .001 and added another .010 to each side (steps are skipped)
What hasn't been set properly ? What also needs to be done to prevent failure?
What happens to a pulling trucks diff as it nears the end of a run , that happens to a drag cars diff at the beginning of a run... and weight doesn't mean anything.
.
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takedown95
New member
Can you show me the physics between the two applications where the mass of 40k of weight doesn't increase the force applied?
YoungDiesel27
Never Enough Time
Supershafts, you think that if one of us filled block, one ton driveline 1200hp+ Pullers sent you a complete differential and you did what ever you want with it...it will last if we promise to bust laps Around the track before we pull??
What steps am I missing? After setting it up I ran a contact pattern and the drive and coast were centered top to bottom and side to side. Yes the pinion bearing preload was 35 in lbs and the added shiims on the side of the carrier were there so the carrier just didn't fall into the housing since I don't have a spreader.
SledPuller21
Never enough
Supershafts
We race, so You win
Jacking it up is good to get the oil to temp, that is helpful.
SledPuller21 said:
So you're saying you can't do anything to make a heat cycle on it...
.
Supershafts
We race, so You win
You want the gear to be more on the toe than center on the drive side in apps where loads are more than normal. Center of tooth top to bottom is good (root to crown)
DISTURBED
YEA WE RIDE THE SHORT BUS
Not really unless your doing it with a torch before you install it. I don't think you understand the kind of stuff we run. They aren't built to drive around. They are meant to go 300' WFO and that's it. You cant put them on jack stands and let them idle till the diff gets hot. Not to mention, doing it every time before they hook. Some use to put heaters on the out side of the diffs to get the oil warm and that was a waist of time.
madmikeismad
So mad
I still don't get how weight matters that much to gears. I imagine the spinning in the dirt and traction gain/loss hurts more than anything. If you weren't spinning, it wouldn't be any different than just pulling a heavy trailer right?
Or, is the r/p just the weakest link since you guys run fancy axle and drive shafts?
Or, is the r/p just the weakest link since you guys run fancy axle and drive shafts?
GOT-Torque
is
Ring and pinion is the weak link right now. If anyone thinks the gears get lightly loaded at the line and progressively get heavier in a nice linear fashion as you go down the track then you have obviously never been in a pulling truck. You can literally feel it in the truck as it fights to get traction on a good track. You can even look at the datalogs and see how rpm varies up and down as it comes down the track. Compaction, soil type, tire air pressures, dips in the track, etc all play a role. I think the loading and unloading of the gears makes matters worse. The more backlash you have in your drivetrain, the more it can wind up before slamming together again.
takedown95
New member
Basic equation for force: Force=Mass*Acceleration
Baddest diesel drag truck on the planet equals the acceleration of a top fuel dragster=4.2gs and has a Mass of 2900kgs
Diesel pull truck accelerates at a very weak 0.5gs and has a Mass (with sled) of 26000kgs.
Force of drag truck =4.2X2900=12,180
Force of pulling truck=0.5X26000=13,000
Even with the most ridiculous acceleration estimate for a drag truck the force on gears is greater with a pulling truck.
In terms of your trailer pulling question....rev your truck up to 5000 rpms and drop the clutch in the dirt and then try slipping out the clutch a bit and accelerating slowly and tell me which one feels more violent. LOL
madmikeismad
So mad
That's what I was trying to ask. Thank you.