Granite Granite 3S- high pitched whining noise

[Coredog22]

Hey Guys,

I bought a Granite a few weeks ago. So far I love it, it takes a pretty good beating.

Yesterday evening I was running a battery down to storage charge it and put it away. While ripping around my yard, it was standing a wheeling heading out to the street. Thankfully the streets in my neighborhood do not have curbs, but there is still a lip from the easement to the street. While doing the wheelie it the lip pretty hard and tumbled in to the street.

I hooked the battery back up and everything came back alive again but when I gave it throttle the wheels did not coast to a stop, more like came to stop like there was an added resistance now and a high pitched whine when hitting the throttle. I took the slipper apart and checked it out, it does not look like there is anything wrong with the gears, I meshed them again, bearings move freely and do not feel gritty like they are trashed, I just reassembled it and it is still making this high pitched squeal. Any ideas on what this might be?

 

[Velodromed]

Hey Guys,

I bought a Granite a few weeks ago. So far I love it, it takes a pretty good beating.

Yesterday evening I was running a battery down to storage charge it and put it away. While ripping around my yard, it was standing a wheeling heading out to the street. Thankfully the streets in my neighborhood do not have curbs, but there is still a lip from the easement to the street. While doing the wheelie it the lip pretty hard and tumbled in to the street.

I hooked the battery back up and everything came back alive again but when I gave it throttle the wheels did not coast to a stop, more like came to stop like there was an added resistance now and a high pitched whine when hitting the throttle. I took the slipper apart and checked it out, it does not look like there is anything wrong with the gears, I meshed them again, bearings move freely and do not feel gritty like they are trashed, I just reassembled it and it is still making this high pitched squeal. Any ideas on what this might be?

Sounds like it was an impact underneath towards the rear from the way you described it. You may have shifted the motor in the mount, tightening the mesh hard. Or done something to the rear differential. I would check the motor mount situation first since it’s relatively easy to get to. Then the rear differential area.

 

[Coredog22]

Sounds like it was an impact underneath towards the rear from the way you described it. You may have shifted the motor in the mount, tightening the mesh hard. Or done something to the rear differential. I would check the motor mount situation first since it’s relatively easy to get to. Then the rear differential area.

Thanks for the info, I have never had an RC with a slipper clutch and motor assembly like this one.

The motor mount looked ok when I removed the power module yesterday. When I get home tonight, I will take the power module out again and remove the motor from the mount to get a closer look at it.

Do you know off hand what weight diff oil the granite takes? I did not see the weight listed in the online manual.

 

[Velodromed]

When you remove the motor mount, simply put it on a flat hard surface to see if there is a slight bend. They are easy to hammer straight again. If you want a good reasonably priced mount get one off of Jenny‘s ($20 plus $6 shipping, so get other parts as well) for the 4s Kraton/outcast, the 3S infraction and vendetta. They are 6 mm thick instead of five. I’m impressed at how strong they are. I’ve had one on my granite for several months. I like to jump it and haven’t manage to bend it yet, even at the skate park. I also put a couple 36 mm diameter, 2.5-3mm thick o-rings around the end of the motor can to help keep it from flexing and hitting the chassis during jumps.

Stock differential oil weight is 10k cst. There are two forms of oil viscosity rating. Weight and CST. Don’t get them mixed up because they’re drastically different. For example, 50 weight oil is 710 CST. 10K cst means 10,000 cst. I tend to get shock oil in weights, 55-60 weight seems perfect for the 3S line (I think stock is 45 to 50). The differential oil always seems to come in CST. I like 15-20 K in the rear and 25-30 K upfront.

I go by ‘approximates’ pretty much. I don’t like to waste the stock oils and since the diffs only come around half-2/3rds full from the factory (same with shocks), I top them off with a heavier weight to get my ‘approximates’. I figure they only partially fill them because these things are often air shipped and pressure causes issues (over flow/blown seals). Oils are also expensive also, so I’m sure they save money.

Anyway, bottom line is these cars are bashers, not race machines. There are also primarily composite plastics so they’ll be some warping etc from the factory, at times, and definitely from use. So there’s going to be slop in the steering/wheels and other minor issues that’ll drive you crazy if you try to fix them

 

[Hector_Fisher]

Based on the description, i'd suspect a bent motor mount. If you're sure you re-meshed it fine (and double checked again after the power module case was snapped shut) then it's likely the motor mount that's preventing good, flat gear engagement.

The only other high pitch noises i'm familiar with on these trucks is 1) a loose slipper clutch, 2) bad bearings (particularly motor or slipper bearings), 3) bad mesh caused by poor mesh setting or other damage. Start there and see if you can find anything

 

[Coredog22]

When you remove the motor mount, simply put it on a flat hard surface to see if there is a slight bend. They are easy to hammer straight again. If you want a good reasonably priced mount get one off of Jenny‘s ($20 plus $6 shipping, so get other parts as well) for the 4s Kraton/outcast, the 3S infraction and vendetta. They are 6 mm thick instead of five. I’m impressed at how strong they are. I’ve had one on my granite for several months. I like to jump it and haven’t manage to bend it yet, even at the skate park. I also put a couple 36 mm diameter, 2.5-3mm thick o-rings around the end of the motor can to help keep it from flexing and hitting the chassis during jumps.

Stock differential oil weight is 10k cst. There are two forms of oil viscosity rating. Weight and CST. Don’t get them mixed up because they’re drastically different. For example, 50 weight oil is 710 CST. 10K cst means 10,000 cst. I tend to get shock oil in weights, 55-60 weight seems perfect for the 3S line (I think stock is 45 to 50). The differential oil always seems to come in CST. I like 15-20 K in the rear and 25-30 K upfront.

I go by ‘approximates’ pretty much. I don’t like to waste the stock oils and since the diffs only come around half-2/3rds full from the factory (same with shocks), I top them off with a heavier weight to get my ‘approximates’. I figure they only partially fill them because these things are often air shipped and pressure causes issues (over flow/blown seals). Oils are also expensive also, so I’m sure they save money.

Anyway, bottom line is these cars are bashers, not race machines. There are also primarily composite plastics so they’ll be some warping etc from the factory, at times, and definitely from use. So there’s going to be slop in the steering/wheels and other minor issues that’ll drive you crazy if you try to fix them

Thanks, I appreciate the info.

I will take a look at the motor mount and see if it is out of flat. The motor mounts on Jenny's RC are thicker than the one that comes with it? the look almost the same from the one I had seen. Do you have a link to the thicker one?

I will keep that in mind for the oils as well. I ordered diff oil today, I will be digging in to the back one to see if I can find anything wrong with it if I can't find the noise in the power module.

Definitely bashers and get the crap beat out of them lol. I definitely am not looking to make the Granite in to a finely tuned race car, this noise just strikes me as something is wrong and I am not familiar with slippers and the noises they can make.

Based on the description, i'd suspect a bent motor mount. If you're sure you re-meshed it fine (and double checked again after the power module case was snapped shut) then it's likely the motor mount that's preventing good, flat gear engagement.

The only other high pitch noises i'm familiar with on these trucks is 1) a loose slipper clutch, 2) bad bearings (particularly motor or slipper bearings), 3) bad mesh caused by poor mesh setting or other damage. Start there and see if you can find anything

Sounds good, thanks for the info.

When you say motor bearing are you talking about the bearing actually inside the motor? or the one nearest to the motor in the gearbox?

 

[Hector_Fisher]

Thanks, I appreciate the info.

I will take a look at the motor mount and see if it is out of flat. The motor mounts on Jenny's RC are thicker than the one that comes with it? the look almost the same from the one I had seen. Do you have a link to the thicker one?

I will keep that in mind for the oils as well. I ordered diff oil today, I will be digging in to the back one to see if I can find anything wrong with it if I can't find the noise in the power module.

Definitely bashers and get the crap beat out of them lol. I definitely am not looking to make the Granite in to a finely tuned race car, this noise just strikes me as something is wrong and I am not familiar with slippers and the noises they can make.

Sounds good, thanks for the info.

When you say motor bearing are you talking about the bearing actually inside the motor? or the one nearest to the motor in the gearbox?

Motor bearings are the ones inside the motor can. If you post a video (usually youtube works best) of the noises, we can help try to diagnose.

 

[Velodromed]

The motor mounts on Jenny's RC are thicker than the one that comes with it

Just some of them are on the new 3/4s cars that have come out over the last year or so. The vendetta, 3s infraction, 4s OutKast and Kraton. All 4 have a 6 mm mount. Here’s a link to the one from the 3s infraction, it is in stock. That 1 mm difference between this one and the old one, plus whatever else they did to make this one stronger, is a big difference in durability. I have been running one in my granite that I like to jump and it’s been very strong. Since you’re going to pay 5-6+ bucks shipping regardless of getting one part or several might as well get some driveshaft, arms and hubs. Those are the three things that seem to break the most.

https://jennysrc.com/collections/ar...inum-mount-motor-fan-granite-senton-ara4319v3

 

[Coredog22]

Motor bearings are the ones inside the motor can. If you post a video (usually youtube works best) of the noises, we can help try to diagnose.

Definitely a bent motor mount on that was the noise. I took the motor mount off, it had about a 1/8" dish. I beat it back in to shape and it is quieter than what it was when I took it out of the box. Thanks for pointing me in the right direction.

Just some of them are on the new 3/4s cars that have come out over the last year or so. The vendetta, 3s infraction, 4s OutKast and Kraton. All 4 have a 6 mm mount. Here’s a link to the one from the 3s infraction, it is in stock. That 1 mm difference between this one and the old one, plus whatever else they did to make this one stronger, is a big difference in durability. I have been running one in my granite that I like to jump and it’s been very strong. Since you’re going to pay 5-6+ bucks shipping regardless of getting one part or several might as well get some driveshaft, arms and hubs. Those are the three things that seem to break the most.

https://jennysrc.com/collections/ar...inum-mount-motor-fan-granite-senton-ara4319v3

View attachment 267214

Awesome, thanks. I will get one of these on order. A bent motor mount was the culprit.

 

[Velodromed]

Definitely a bent motor mount on that was the noise. I took the motor mount off, it had about a 1/8" dish. I beat it back in to shape and it is quieter than what it was when I took it out of the box. Thanks for pointing me in the right direction.

Awesome, thanks. I will get one of these on order. A bent motor mount was the culprit.

just remember it’s only those 4 cars that have the new mount. 4s Kraton/outcast and 3s infraction/vendetta. Glad you got it figured out!

 

[Hector_Fisher]

You can either get than 6mm part from jennys, or you can order the specific part if needed: ARA311106 is the 6mm motor plate.