59840Surfer
Full Access Member
- Joined
- Oct 8, 2020
- Posts
- 206
- Reaction score
- 335
- Location
- Montana
- First Name
- Joe
- Truck Year
- 1986
- Truck Model
- K5
- Engine Size
- 350 Stroker to 383 with a 400 crank, Crane Cam, Q-Jet, single 3.5" exhaust..
I've never worried about or tried to actually correct backlash as it is the end product when everything else is running a good pattern. It's more-or-less WYSIWYG after all else is set up ---> correctly.I am setting up a new ring and pinion in my '73 K10. This is the Dana 44 in the front. The original gears were 3.08, the new gears are 4.11. I think the pattern looks OK but I could use some comments from people with more experience. The backlash is at 0.010". I still need to set the pinion preload, hopefully that won't change the pattern. I do have preload on the pinion but the nut is not torqued to 200 yet.
Backlash has always been a spooky bugaboo to anyone who doesn't work on differentials --- and a lot of high anxiety/hand wringing is caused by people who don't have the field experience in setting up tooth patterns and clearances.
I've worked on a lot of gearsets - from commercial busses and dump trucks, AWD cement haulers, Cats, OTR tractors, general automotives and passenger cars during my 60+ years and like I said: backlash is or should be the last thing to even look at and (be) generally dismissed as non-controllable and an 'after all else is correct' means-nothing value.
I will note here that higher numerical ratios (4.56:1, 5.08:1, etc., and up) will, by design, have a substantially smaller freeplay when all is set up correctly. It's cooked into the geometry and designed-in necessities of engineering, and as a sidebar it self-defeats attempts to eliminate expensively dragging the greater numerically significant tooth contact over larger surface areas in those ratios, wasting fuel and creating higher heat.
Fuel consumption as a guideline eg: Governmental CAFE Standards - almost condemn numerically high gear ratios as wasteful because of the higher heat/frictional generation ostensibly from the higher pinion speed and inherent friction from sliding over the slower, numerically higher count of the moving ring gear teeth.
This is why we see more of closer to 1:1 ratios to help mitigate heat generation and higher fuel consumption; ultimately, heat comes from your fuel tank.
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