Yukon Gear vs. Revolution Gear for a 14-bolt

[Lanzg]

Well, I spoke to soon. I followed up with the Filthy Motorsports guy - and it tuns out he is the real deal. Ben Brazda - to whom I spoke - is the owner of Filthy Motorsports, and also the owner of Crown Race Gears. He builds a lot of gears setups for Ultra 4 racers, rock bouncers, drag racers, mud drag racers, desert racers, and the like. He certainly was able to demonstrate - at least to me - that he knows what he is talking about.

He spoke with me for quite a while on my issues. He believes my failures may likely be a setup issue, and that for an application like mine I should not be setting it up with a standard pattern that you would use for a GMC truck - which is what I did. He recommends - and does - a much deeper setup much closer to the root to allow for deflection which will invariably occur in high shock-load situations. He actually said that with a deeper setup, even the low-quality Yukon Chinese gears should hold up. He also recommended going with Revolution as another alternative, and that should be fine as well. When I told him I have pictures of my pattern, he suggested that I send them to him and he may be able to provide some insight.

He explained a lot about their processes and how they make their gear sets, as well as the slightly different approaches they take depending on the ultimate application. Desert racing is different than rock crawling and bouncing, etc.

He also said that a simpler solution may be to go down to a 4.88. Yup, he said it. 2 tooth engagement compared to a one tooth engagement for the 5.38's. The cheaper gears would even hold up better in that setup. This has been discussed on the forum often, and Blaine has weighed in as well, but this guy says the 5.38 setup is definitely a little weaker all other factors being consistent. But, the 5.38's can be made strong enough - given the right metallurgy, treatment, and especially setup. He says the vast majority of his Ultra-4 customers run 5.38's.

I asked him specifically about his cryo-processing, and how he avoids getting too brittle of an end result. He said, "Very good question..." which made me feel good. He then explained how it all works in a way that I understood as he was explaining it, but I certainly could not explain it to someone else. Again, he does sound like he knows his stuff, and has been doing this for a long time.

We talked at length about the shaving process he uses, and how they do it in a way which takes into account avoiding heat building, burring, etc. He says they spend about 8 hours to do it correctly. He asked if I knew how Yukon does it, and I responded that I did not, but he thought for the price they charge they probably throw is on a lathe and hack away at it - possibly destroying the heat treatment in the process. He said that was just a guess on his part, but it could result is a weaker gearset.

Ben also warrants his gears for 5 years assuming a proper setup - which he would help me get to and confirm. He also indicated that he could analyze my failed gearset if I sent them to him, and likely would be able to tell me why they failed. I may take him up on that.

All in all, I really enjoyed the conversation with Ben. Although he recommended several less expensive solutions that he thought would meet my needs, I ultimately decided to go with a set of his race gears. He also offered to work with me on the setup when the times comes.

He was not in his shop during our conversation, but he was going to check if they had anything on the shelf which might reduce the 8-12 week lead time.

It's gonna be expensive, but it appears this may be the best approach to providing the best chance to avoid this happening again.

Outstanding, sounds like you are on your way to a solution.

LG

 

[Wildman]

It's gonna be expensive, but it appears this may be the best approach to providing the best chance to avoid this happening again.

Well when you consider how much one set costs plus downtime associated with it I'd say it evens out... Considering how many gear sets both you & I have gone through...

 

[NashvilleTJ]

Outstanding, sounds like you are on your way to a solution.

LG

Well when you consider how much one set costs plus downtime associated with it I'd say it evens out... Considering how many gear sets both you & I have gone through...

I forgot to mention that Filthy also sells Revolution Gear sets. He actually sent me a link to the 5.38 thick cuts that he resells. He indicated they they could also do the shaving, but that they take their time and do it right to preserve the heat treating on the original. He estimated that all in he would likely be around $700 for that approach. So, I'm really comparing $1300 for the race gears to $700 for the Revolution. Easier to digest when I look at it that way.

And by the way, the last time I looked the shaved 14-bolt gearset from Yukon was about $500.

 

[Wildman]

I forgot to mention that Filthy also sells Revolution Gear sets. He actually sent me a link to the 5.38 thick cuts that he resells. He indicated they they could also do the shaving, but that they take their time and do it right to preserve the heat treating on the original. He estimated that all in he would likely be around $700 for that approach. So, I'm really comparing $1300 for the race gears to $700 for the Revolution. Easier to digest when I look at it that way.

And by the way, the last time I looked the shaved 14-bolt gearset from Yukon was about $500.

Good luck either way... You're the Test Dummy.... So if/when I break my CRD60 (again) I'll know which way to go....

 

[mrblaine]

He says the vast majority of his Ultra-4 customers run 5.38's.

If they were actually a little weaker enough to make a difference, that wouldn't be possible and there isn't much else after that. If it was an actual problem, the only way to fix it for the Ultra 4 folks would be to not run them.

 

[gasiorv]

Guess if you are going to drive it like a bouncer, might as well build it like a bouncer.

 

[mrblaine]

Guess if you are going to drive it like a bouncer, might as well build it like a bouncer.

Their tires are bigger, they don't weigh as much, and they have twice as much horsepower, but other than that, yeah, build it like a bouncer.

Minor parallel, when we run HP in the rear, we have our gear guys run the pattern so when it deflects under load, it moves into a more correct pattern that slows down how much it tries to break off the ends of the teeth.

Lest we forget, the bouncers will generally run a few miles, little of it on big rocks. The Ultra 4 rigs will put the gear sets through impact loads slamming over the rocks many 100's of times per race. The below is a small example of part of 1 trail, several racers, all subjecting the gear sets to brutal impact loads.

It is not uncommon to see the race rigs on jack stands running in gear to warm up the high viscosity gear oil.

 

[NashvilleTJ]

...

It is not uncommon to see the race rigs on jack stands running in gear to warm up the high viscosity gear oil.

That's something that Ben told me as well. He said he's also seen those boys heating their diffs with a torch to warm them up. Different world.

 

[mrblaine]

That's something that Ben told me as well. He said he's also seen those boys heating their diffs with a torch to warm them up. Different world.

All you would have to do is stick a freeze plug hole in the diff casting and fill it with an OEM block heater.

 

[Woodrow]

Their tires are bigger, they don't weigh as much, and they have twice as much horsepower, but other than that, yeah, build it like a bouncer.

Minor parallel, when we run HP in the rear, we have our gear guys run the pattern so when it deflects under load, it moves into a more correct pattern that slows down how much it tries to break off the ends of the teeth.

Lest we forget, the bouncers will generally run a few miles, little of it on big rocks. The Ultra 4 rigs will put the gear sets through impact loads slamming over the rocks many 100's of times per race. The below is a small example of part of 1 trail, several racers, all subjecting the gear sets to brutal impact loads.

It is not uncommon to see the race rigs on jack stands running in gear to warm up the high viscosity gear oil.

Oof…

 

[Woodrow]

Well, I spoke to soon. I followed up with the Filthy Motorsports guy - and it tuns out he is the real deal. Ben Brazda - to whom I spoke - is the owner of Filthy Motorsports, and also the owner of Crown Race Gears. He builds a lot of gears setups for Ultra 4 racers, rock bouncers, drag racers, mud drag racers, desert racers, and the like. He certainly was able to demonstrate - at least to me - that he knows what he is talking about.

He spoke with me for quite a while on my issues. He believes my failures may likely be a setup issue, and that for an application like mine I should not be setting it up with a standard pattern that you would use for a GMC truck - which is what I did. He recommends - and does - a much deeper setup much closer to the root to allow for deflection which will invariably occur in high shock-load situations. He actually said that with a deeper setup, even the low-quality Yukon Chinese gears should hold up. He also recommended going with Revolution as another alternative, and that should be fine as well. When I told him I have pictures of my pattern, he suggested that I send them to him and he may be able to provide some insight.

He explained a lot about their processes and how they make their gear sets, as well as the slightly different approaches they take depending on the ultimate application. Desert racing is different than rock crawling and bouncing, etc.

He also said that a simpler solution may be to go down to a 4.88. Yup, he said it. 2 tooth engagement compared to a one tooth engagement for the 5.38's. The cheaper gears would even hold up better in that setup. This has been discussed on the forum often, and Blaine has weighed in as well, but this guy says the 5.38 setup is definitely a little weaker all other factors being consistent. But, the 5.38's can be made strong enough - given the right metallurgy, treatment, and especially setup. He says the vast majority of his Ultra-4 customers run 5.38's.

I asked him specifically about his cryo-processing, and how he avoids getting too brittle of an end result. He said, "Very good question..." which made me feel good. He then explained how it all works in a way that I understood as he was explaining it, but I certainly could not explain it to someone else. Again, he does sound like he knows his stuff, and has been doing this for a long time.

We talked at length about the shaving process he uses, and how they do it in a way which takes into account avoiding heat building, burring, etc. He says they spend about 8 hours to do it correctly. He asked if I knew how Yukon does it, and I responded that I did not, but he thought for the price they charge they probably throw is on a lathe and hack away at it - possibly destroying the heat treatment in the process. He said that was just a guess on his part, but it could result is a weaker gearset.

Ben also warrants his gears for 5 years assuming a proper setup - which he would help me get to and confirm. He also indicated that he could analyze my failed gearset if I sent them to him, and likely would be able to tell me why they failed. I may take him up on that.

All in all, I really enjoyed the conversation with Ben. Although he recommended several less expensive solutions that he thought would meet my needs, I ultimately decided to go with a set of his race gears. He also offered to work with me on the setup when the times comes.

He was not in his shop during our conversation, but he was going to check if they had anything on the shelf which might reduce the 8-12 week lead time.

It's gonna be expensive, but it appears this may be the best approach to providing the best chance to avoid this happening again.

The deeper set up idea makes sense, sort of. But what is the downside or why not do it routinely in a GMC truck as well?

 

[Wildman]

The deeper set up idea makes sense, sort of. But what is the downside or why not do it routinely in a GMC truck as well?

I know when I was doing mine Carl from Jantz had told me to set it up tighter, meaning less backlash and then do short break in runs at first. This was my CRD60 rear with a Super 60 gear set.

 

[Lanzg]

All you would have to do is stick a freeze plug hole in the diff casting and fill it with an OEM block heater.

Gotta heat up the engine oil and the tcase/trans/power steering and on and on, Torpedo heaters and a little time, we did it all at once. I wasn't going to sleep that night anyway.

Starting a race with a 23 degree front pump seal in the transmission and just blasting it off the line can make for a short day.

LG

 

[mrblaine]

Gotta heat up the engine oil and the tcase/trans/power steering and on and on, Torpedo heaters and a little time, we did it all at once. I wasn't going to sleep that night anyway.

Starting a race with a 23 degree front pump seal in the transmission and just blasting it off the line can make for a short day.

LG

Easy way to dispense with all that nonsense is just don't put any oil in the diffs. I wish that weren't true and I'm just being funny. Not once, twice.

 

[Lanzg]

Easy way to dispense with all that nonsense is just don't put any oil in the diffs. I wish that weren't true and I'm just being funny. Not once, twice.

I feel this so deep.....
Run out of gas still with in sight of pit....
Backed off nut on alternator......

God I don't miss that shit.
LG

 

[NashvilleTJ]

I posted this over in my build thread, but wanted to post it here as well since there was an ongoing discussion:


Quick update on the R&P situation. I've spoken a few more times to Ben over at Filthy Motorsports. He did go back and check his inventory, and he actually had on hand a fully treated and shaved 14 bolt thick cut 5.38 R&P. He checked the history on it and said they had built and shaved it for racer customer a while back, but somewhere along the line the edge of one of the bearing surfaces on the pinion was nicked slightly. They were able to polish it out, but it was marked as "blemished," and they wound up doing another set for that customer as he was paying for a perfect gear set. Ben told me he could have sent it on to his customer and he never would have known. Sounds like Ben has some good customer service practices.

Ben checked all the specs on the pinion, everything measures out fine, and would work perfectly. Given the history, he said he would sell it to me for $750, and still warrant it. The $'s saved is certainly a plus, but the big deal is losing the long lead time. So, it's on its way to me.

From what Ben told me he could easily have not disclosed the history and sold it to me as new. Instead, he was honest. That builds trust, and that I respect.

I also sent Ben some pics of the last failed pinion, along with pics of the final pattern. He said the pattern looked good, but would have gone just a little deeper. But, he said the failure looked more like a debris failure, rather than shock load or deflection. That got me thinking:

I shaved this sissy 14-bolt myself, and welded on the AR500 plate to the bottom. Here is the case at the time of the last failure.

See that little bit of weld spatter at the bottom? When I shaved this sissy 14-bolt, I went in and aggressively chipped off all of that that would come up. What remained would not come off even whacking it hard with a cold chisel. I obviously did not think the remaining spatter would come off and cause a problem.

But given the two failures, now I'm thinking maybe with heating and cooling cycles a few of those pebbles could have come loose. I think one of those hardened beads going through would definitely cause some harm.

I've always said I was a hack.

Any thoughts as to whether this could be the case?

Regardless, when I get back in there I'll hit it with a rotary grinder and get rid of every one of those pebbles (grenades?).

 

[hosejockey61]

I posted this over in my build thread, but wanted to post it here as well since there was an ongoing discussion:


Quick update on the R&P situation. I've spoken a few more times to Ben over at Filthy Motorsports. He did go back and check his inventory, and he actually had on hand a fully treated and shaved 14 bolt thick cut 5.38 R&P. He checked the history on it and said they had built and shaved it for racer customer a while back, but somewhere along the line the edge of one of the bearing surfaces on the pinion was nicked slightly. They were able to polish it out, but it was marked as "blemished," and they wound up doing another set for that customer as he was paying for a perfect gear set. Ben told me he could have sent it on to his customer and he never would have known. Sounds like Ben has some good customer service practices.

Ben checked all the specs on the pinion, everything measures out fine, and would work perfectly. Given the history, he said he would sell it to me for $750, and still warrant it. The $'s saved is certainly a plus, but the big deal is losing the long lead time. So, it's on its way to me.

From what Ben told me he could easily have not disclosed the history and sold it to me as new. Instead, he was honest. That builds trust, and that I respect.

I also sent Ben some pics of the last failed pinion, along with pics of the final pattern. He said the pattern looked good, but would have gone just a little deeper. But, he said the failure looked more like a debris failure, rather than shock load or deflection. That got me thinking:

I shaved this sissy 14-bolt myself, and welded on the AR500 plate to the bottom. Here is the case at the time of the last failure.

View attachment 659129


See that little bit of weld spatter at the bottom? When I shaved this sissy 14-bolt, I went in and aggressively chipped off all of that that would come up. What remained would not come off even whacking it hard with a cold chisel. I obviously did not think the remaining spatter would come off and cause a problem.

But given the two failures, now I'm thinking maybe with heating and cooling cycles a few of those pebbles could have come loose. I think one of those hardened beads going through would definitely cause some harm.

I've always said I was a hack.

Any thoughts as to whether this could be the case?

Regardless, when I get back in there I'll hit it with a rotary grinder and get rid of every one of those pebbles (grenades?).

Wow great to hear about that customer service!

I would definitely go back in and clean up what you can as far as that splatter. Very feasible that was the culprit. Did you learn to weld from @jjvw?

 

[NashvilleTJ]

Wow great to hear about that customer service!

I would definitely go back in and clean up what you can as far as that splatter. Very feasible that was the culprit. Did you learn to weld from @jjvw?

Now, that was just mean, Mike...

 

[Brianj5600]

When you set up a shaved gear set, do you set the pattern on the ring gear in the middle drive side or the a 1/4" from the middle of the tooth?

 

[mrblaine]

The pinion teeth by design are stronger than the ring gear teeth. If this is a debris failure, then there should be corresponding damage on the ring gear teeth.