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Old 04-26-2015, 12:18 PM   #1501
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Since having to tighten the diff to the max when running mod (so as to not bark the diff) and run a tight slipper (due to the weight of the truck), I am wondering if the benefits (tuning and weight) of a ball diff vs gear diff are being lost. Also rebuild requirements go way up with a 7.5 vs 17.5. Comments please.
No they don't. I've ran an aggressive modified motor for months without having to touch a diff that was and stayed absolutely cherry.

That said, a slipper is more than a tuning tool for eliminating wheel spin, it also is there to relieve shocks to the drivetrain. I would recommend properly setting your slipper for a slight amount of slip. Even in 17.5 class, you're going to want some give in the drive train for shocks and bumps. I've ran Alloy pucks with a 7.5 turn motor, and never had abnormal wear or exploded anything. I also set my slipper to give up just a little when on the bench, this way the entire drive train isn't being hammered.

The diff should not ever be locked down, it should always be smooth and relatively free - locking it down will give you adverse handling.

If you think a gear diff is a fix for your issue, you're in for a harsh reality - They too will explode when pushed too hard just like a ball diff.
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Old 04-26-2015, 12:33 PM   #1502
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thanks for the info. assembled mucho ball diffs so comfortable that procedure and understanding is good to go. I use carbide or ceramic balls and same for thrust. got away from sanding after talking to one of the ae drivers. will try sanding before I assemble today and check results. thanks again.
You can not beat a properly built and tuned carbide based ball diff. It should and can last at least a year regardless of the motor and application it's in. The B5M/T5M diff is one of the smoothest around, and most durable when setup correctly. It continues to sound like you're not able to setup the drivetrain correctly, and are faulting the diff for this.
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Old 04-26-2015, 03:32 PM   #1503
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You can not beat a properly built and tuned carbide based ball diff. It should and can last at least a year regardless of the motor and application it's in. The B5M/T5M diff is one of the smoothest around, and most durable when setup correctly. It continues to sound like you're not able to setup the drivetrain correctly, and are faulting the diff for this.
Ball diff on my 17.5 lasts about 4 months. Longevity depends on how much you race and practice. I race 3 times a week so they get plenty of use. Mod ball diffs in a truck do not last as long as stock 17.5 buggy diffs in my experience. Quite a bit of weight difference between the 2 vehicles and lots more stress on the mod diff. Have always ran mod and was pleased with how long a stock 17.5 ball diff in a buggy lasts. Not faulting ball diffs at all. Just wanted some feedback on what folks experienced about running ball diffs in 7.5 mod motors and a heavy truck. Have built lots and lots of ball diffs so no problem regarding how to build. Just finished breaking in and ready to install.
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Old 04-26-2015, 03:36 PM   #1504
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I agree I did not like ball diffs until I learned how to properly build one. Get some b fast diff rings and balls you will be happy.
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Old 04-26-2015, 03:43 PM   #1505
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No they don't. I've ran an aggressive modified motor for months without having to touch a diff that was and stayed absolutely cherry.

That said, a slipper is more than a tuning tool for eliminating wheel spin, it also is there to relieve shocks to the drivetrain. I would recommend properly setting your slipper for a slight amount of slip. Even in 17.5 class, you're going to want some give in the drive train for shocks and bumps. I've ran Alloy pucks with a 7.5 turn motor, and never had abnormal wear or exploded anything. I also set my slipper to give up just a little when on the bench, this way the entire drive train isn't being hammered.

The diff should not ever be locked down, it should always be smooth and relatively free - locking it down will give you adverse handling.

If you think a gear diff is a fix for your issue, you're in for a harsh reality - They too will explode when pushed too hard just like a ball diff.
thanks for the input. Never had a gear diff explode but am an expert on replacing idler gears on an sc10 ha ha. I run a slipper eliminator on my stock buggy with no problem. Staying off power on jumps takes care of the situation and makes for much faster lap times. I typically back off my diff a bit so as to not lock it down but it is still very tight. Had a problem with the t5m stock slipper tightening correctly so replaced with a b5m slipper. ae factory driver had the same prob so both faulty slippers went back to ae for eval. Maybe I will bite the bullet a get a schelle.
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Old 04-26-2015, 03:46 PM   #1506
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thanks for the input. Never had a gear diff explode but am an expert on replacing idler gears on an sc10 ha ha. I run a slipper eliminator on my stock buggy with no problem. Staying off power on jumps takes care of the situation and makes for much faster lap times. I typically back off my diff a bit so as to not lock it down but it is still very tight. Had a problem with the t5m stock slipper tightening correctly so replaced with a b5m slipper. ae factory driver had the same prob so both faulty slippers went back to ae for eval. Maybe I will bite the bullet a get a schelle.
The schelle is heads and shoulders above both the 2 pad and the VTS. I tried to run the 2 pad on a previous truck, and it was a mess. It either slipped like crazy, or would bark the diff.
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Old 04-26-2015, 04:54 PM   #1507
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thanks for the confirmation. will pick up a schelle before I put it on the track.
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Old 04-26-2015, 10:31 PM   #1508
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using the stock setup is it just me or to get 30mm ride hide does one really need to tighten the shock collars a lot? On the front mine are almost to the end of the threads.
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Old 04-26-2015, 10:56 PM   #1509
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using the stock setup is it just me or to get 30mm ride hide does one really need to tighten the shock collars a lot? On the front mine are almost to the end of the threads.
yep mine are the same.
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Old 04-26-2015, 11:01 PM   #1510
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use the 9mm shock spring cups
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Old 04-27-2015, 03:46 AM   #1511
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thanks for the info. thought lighter gear diff oil would eliminate locking effect.
no, the locking effect is the gears wanting to seperate under load and then they bind against the housing.

the oil basicly just softens or hardens the low speed diff action, when you start puting alot of power down they tend to behave the same regardless of the oil weight.
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Old 04-27-2015, 03:48 AM   #1512
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i've seen people say the truck bounces from time to time,

mine does this too on a low jump with flat landing sometimes.

is there a way to completely eliminate this? played around with pistons but it seems the bounce doesn't ever go away.
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Old 04-27-2015, 06:17 AM   #1513
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Ran my truck this weekend and tq'd and won stock truck at a local track. First time on the layout and the truck was ridiculous! Mounted a fan on the trans case facing the motor and it dropped my temps dramatically. If you guys are running stock I really recommend doing it!
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Old 04-27-2015, 08:21 AM   #1514
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i've seen people say the truck bounces from time to time,

mine does this too on a low jump with flat landing sometimes.

is there a way to completely eliminate this? played around with pistons but it seems the bounce doesn't ever go away.
Sounds like it could be a tire issue. How many holes do you have in the tire/rim and where are they? Any holes in the foam?
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Old 04-27-2015, 08:32 AM   #1515
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My T5m came in on Friday.. Went and picked it up on Saturday, had it completely built by Sunday. REALLY easy build. I can see that they put a lot of effort into designing this thing. Anything that does break, should be relatively easy to fix. I don't need to take the whole back of the car apart to re-build the diff or replace the rear arms.. YAY!! I really like the fact that I only needed 2 different allen drivers for the entire truck.

The truck seems to be built like a tank. Can't wait to get it out on the track. All I need is another receiver, wheels/tires and paint for the body..
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