Kraton v5 abysmal turning radius. Did I cause this?

DarkOwl

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I have been driving a stampede 4x4 for 5 years and never had an issue with the turning radius. Never even gave it a thought. Now I have a v5 kraton that I built into a full m2c beefcake plus diff rebuild. I took it out for it's maiden voyage today and discovered that my entire parking lot is not big enough to turn this kraton around. I'm talking about a 30 foot turning radius at any speed above 5mph. I have the Amazon special 35kg servo in there which many forum users swear by, and I have also had great success with a Power HD servo in my stampede. I also set my servo endpoints to maximum, minus one click. So this leaves differentials as the problem, I think. I put 100k in the front, and then 1 million in the center and rear. I thought 1 million was pretty light in the center considering that many ppl use silicon earplugs. The biggest problem for me is that I didn't run the truck before rebuilding the diffs. Can anyone give me advice about my turning radius or advice I diff oil weight? I could easily swap my front and rear differentials if that could help.
 

DarkOwl

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Sounds like your front and rear fluids are way too high. I run 10K in the rear and 30K in the front.
In that case I'll just swap my front and rear diffs and see if that helps. 10k seems a bit light. I run 50k in my pede and it's perfect. I could always put the 50k in the kraton as a last resort but it's a lot of work. I just wanted good traction. I got tired of diffing out while climbing stuff.

Also you didn't mention the center. Does the center diff not affect turning radius.
1 mil in the rear is WAAAAAYYY too heavy. Rear diff fluid should be less than the front. Approximately half of the front diff, depending on what driving characteristics you want.
Ok thank you. Is this what affects turning radius?
 

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In short, yes you caused this to happen ;)
Diff fluids are way too high, just like others suggested.
Front 30-50k, rear 20-30k and it will make your life simpler. Middle 300- 500k but doesn't really impact steering with lower fluids. With high fluids you are on rails.

Did you look at your servo saver? Place it on the grass and compare wheel movement to servo movement. Most likely your servo saver is eating 90%. Known V4/V5 issue.
 

DarkOwl

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In short, yes you caused this to happen ;)
Diff fluids are way too high, just like others suggested.
Front 30-50k, rear 20-30k and it will make your life simpler. Middle 300- 500k but doesn't really impact steering with lower fluids. With high fluids you are on rails.

Did you look at your servo saver? Place it on the grass and compare wheel movement to servo movement. Most likely your servo saver is eating 90%. Known V4/V5 issue.
Servo saver does seem too loose to be honest. Before I even ran the truck I swapped out the stock steering rack for the EXB version which includes a beefier spring. I gave it a little crank with pliers before installing it just to be sure and it felt very tight so I didn't really move it. But now the wheels don't turn that well on carpet while the servo sounds strong. Darn. It such a chore getting to that servo saver.
 

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Everyone saying that 50k front 30k rear is perfect and that anything higher is too much should know that some of us run much higher and don't have issues.

In fact Rich Duperdash, one of the hardest bashers I've seen of the Kraton 8S EXB, runs 1m/20m/500k f/c/r. <--- Check out his video. I Personally run 100k/1m/80k f/c/r in my Kraton 6S EXB.

There is always more than one way to do things.

Edit: Edited my reply cause I think I may have sounded a bit snarky. Which was not at all my intention.
 
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DarkOwl

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Everyone saying that 50k front 30k rear is perfect and that anything higher is too much needs to relax and realize that some of us run much higher and don't have issues.

In fact Rich Duperdash, one of the hardest bashers of the Kraton 8S EXB, runs 1m/20m/500k f/c/r. <--- Check out his video. I Personally run 100k/1m/80k f/c/r in my Kraton 6S EXB.

You guys should know by now that is always more than one way to do things.
Yeah I guess it just depends on desired performance. For me, my car is almost undrivable and dangerous to boot. If I was trying to line up at high speed for huge jumps I would probably like this setup lol.
 

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Keep in mind that I was answering for 6S Kraton or 6S line.
8S is a different animal and will run better with higher values, from what I heard.

C-clips for the servo saver, there is no adjustment and cranking anything with pliers will only break stuff.
 

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Servo saver for sure is soft, and needs fixing out of the box. I run 10k-20k rear, because I like to turn where and when I command it. Locked diffs have their place for a certain kind of driver, say, those with an on/off switch for a trigger finger and like doing nothing but mad donuts like a Radio Shack car on ice. Kinda boring if you ask me. Center diff does affect steering, but it is a subtle and complicated relationship best run through trial and error until you figure out your setup.
 

DarkOwl

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Keep in mind that I was answering for 6S Kraton or 6S line.
8S is a different animal and will run better with higher values, from what I heard.

C-clips for the servo saver, there is no adjustment and cranking anything with pliers will only break stuff.
Oh ok, glad I asked! Does anyone have an image of the c-clips or where to put them?
 

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But now the wheels don't turn that well on carpet while the servo sounds strong. Darn. It such a chore getting to that servo saver.
With the car on carpet without the body on, press the front shock tower down and try to steer. have a good look on where you loose the steering. the servo might sound good but it might be too week and you'll see the arm not moving beyond a certein point or something like that.

Again, have a good look to understand what eats your steering. It should turn on a dime with that EXB SS spring.
 

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You can also get the V3 servo saver hub for a few bucks and swap out the nonadjustable V4 - this will allow you to tune the servo saver easier than using clips. Part number is AR340065.

Alternatively there is also the Hot Racing tube with clamping adjuster nut that comes with the spring - part number AON48A02.
 

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I have been driving a stampede 4x4 for 5 years and never had an issue with the turning radius. Never even gave it a thought. Now I have a v5 kraton that I built into a full m2c beefcake plus diff rebuild. I took it out for it's maiden voyage today and discovered that my entire parking lot is not big enough to turn this kraton around. I'm talking about a 30 foot turning radius at any speed above 5mph. I have the Amazon special 35kg servo in there which many forum users swear by, and I have also had great success with a Power HD servo in my stampede. I also set my servo endpoints to maximum, minus one click. So this leaves differentials as the problem, I think. I put 100k in the front, and then 1 million in the center and rear. I thought 1 million was pretty light in the center considering that many ppl use silicon earplugs. The biggest problem for me is that I didn't run the truck before rebuilding the diffs. Can anyone give me advice about my turning radius or advice I diff oil weight? I could easily swap my front and rear differentials if that could help.
On the servo saver these companies cut corners no matter how much we pay that they are so cheap and unnoticeable until you see the white powder from your steering servo. The white bushings in the servo saver should be replaced with bearings. Wheels will turn better even not moving and will help the saver and servo last longer. This is why people always complain about servos. That plastic on plastic grinds, bearings don't. So in my opinion has worked for me and not replacing a servo for up to$100 when the bearings are $5 tops and a little work. Imo. Just found out the hard way with a traxxas rustler 4x4 xl5 while upgrading was replacing my servo saver and found white powder from plastic bushings on plastic poles. Even ohh n the diagram in the manual showed part # and it was a bearing that goes there. Do they purposely do this to have us spend more money replacing things not broke and never notice because even the new savers come with bushings. So I change that first for steering and trying to figure out how to set the endpoints on it. No videos or in manual.
 

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This is 1 of 2 top brands that cut corners (pun intended) on the steering servo saver that people don't and won't notice until they've spent money on a new servo and or servo saver. At the bottom and top of the servo saver are bushings instead of the smallest bearing on the vehicle, which with plastic on plastic will cause friction and eat away at the bushings making steering sloppy and hardly move just sitting still. This will help you from feeling you need to immediately buy a new servo, help the original servo & saver last longer. One brand even shows on the diagram in the manual the # and part for a bearing that is supposed to be in the vehicle, but is not there. Hope this helps. Only time I've had a problem with steering ,out of 8 RCs starting last year, only one had a servo issue and it was warranted out because of the pentameter sticking steering in one direction no matter which way you steered until you backed up then it would work till the next load from turning. Found this out by puting a load on the front while steering it back and forth slowly, if you feel it stop, try to go the other way or wiggle it may be servo pentameter which if you registered it and still have warranty, will be replaced for free. I bought one before the free one came in incase it didnt work was not going back to that servo. But the replacement is fine, as I think individual peices get better QC than the entire vehicle since they can test them. Cant test the car on the ground. Hope this helps. Sorry so long.
 

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Everyone saying that 50k front 30k rear is perfect and that anything higher is too much should know that some of us run much higher and don't have issues.

In fact Rich Duperdash, one of the hardest bashers I've seen of the Kraton 8S EXB, runs 1m/20m/500k f/c/r. <--- Check out his video. I Personally run 100k/1m/80k f/c/r in my Kraton 6S EXB.
Duperdash is the #1 basher, but he doesn't do much hard cornering. His videos are big jumps and high speed straight line over rough terrain, his rigs are set up for this. His setup may not be the one to follow for tight turning radius. His Granite may land big jumps well, but mine corners better.
 
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