Well, I was running my Geni at my Dad's house to show off in front of my nephews and hit a pole mid-air. I haven't disassembled the truck yet to see what my shopping list (quick visual inspection says a-arm, bulkhead) will be but I have a question about torque steering. What happened was I built a ramp out of snow. The ramp was between a tree and a pole. I had at least 7' clearance on either side of the jump and thought that was enough room. Well I'd get the truck moving about 1/2 throttle and just before I'd hit the ramp (still on the concrete driveway) I'd go full throttle. Well when I did this the truck pulled hard to the right and I hit the pole. I was more happy I damaged the truck and didn't take the pole out . LOL. Well, what can I do to resolve this? I read a post from ThermalRD about putting different weight oils in the differentials. Do this help torque steer? ThermalRD, if you read this what weight oils are you running and in what differentials?

I'm surprised I hadn't broken anything sooner as I am a really bad driver. This is a true testament to how tough this truck is!!

Thanks,

Joe

This may also be a servo, and servo saver related problem. This truck has alot of power, you may need to tighten up the servo saver. Careful not to go too tight. You can kill a servo FAST! Now, if your trucks diffs are untouched, then they likely have grease in them. You may be pulling bad to one side on power due to the unloading of the diffs. You would know this by one tire ballooning up more than the opposing side under full power. And it may be a combination of the above. In my experience, the JR servo i ran with 188oz of torque kept the truck under ALOT better control, than the stock servo. I'd say to start with the diffs. You could easily do 10k front and rear, with 30k in the center. You could also do 30k all the way around. Depending what you're using the truck for. The heavier you go in the center, the less steering you'll have. As it will become more like a LOCKED diff. Hope that helps some.

Great, thanks for the info. I may just replace the servo as long as I've got everything apart to replace parts and change from grease to oil. I mainly use my truck just for bashing. My LHS just built a new track so I may take it there and give that a try.

How much oil do you put in the differentials?

Do you have a part number for the servo you ran? And is it compatible with the factory Airtronics radio?

-Is it this one JRPSZ8550? Cheapest I could find it was $97. Does that sound right?
-How about the Hitec HSC-5998TG? Would that also be a good replacement?

I've noticed that when I apply full power that one front wheel or the other picks up off the ground and it pulls to that side. From what you said that sounds like the diffs are unloading.

that same thing happend to me! ! was driving my mt2 to the jump at about 1/2 throttle, i only gave it about 3/4 throttle when the truck slid to the right. but it wasnt a pole i hit it was my older brother

Doh, Hopefully he wasn't like my older brother when we were younger. He would've beat the heck out of me!! LOL.

he came after me but, didnt kill me(he was pretty suprised and didnt realy know what happed, so im pretty lucky)

Well my parts list continues to grow. Before I hit the pole I got it stuck underneath a mini van parked in the driveway. I didn't think much of it at the time. Apparently sudden stoppages really cause a lot of damage. Here is a list of the parts so far including the a-arm from the pole incident:

GS033 Suspension Arm Set
GS048 Upper Bracket

GS094 Output Shaft
GS006 46T Center Diff Gear
G73914 Bearing (this is the bearing that supports the Center Diff Gear)
GS009 Pin Assy (the pin on the front sliding drive shaft is beat up pretty good, not broke but not pretty either)
G73916 Bearing to support the main shaft on the tranny (it feels like mostly water damage, nothing serious but I don't want it to seize and take out my main shaft)

Here are some pics of the carnage:

Output Shaft: http://i7.photobucket.com/albums/y26...1-1199_IMG.jpg
http://i7.photobucket.com/albums/y26...1-1198_IMG.jpg
http://i7.photobucket.com/albums/y26...1-1200_IMG.jpg

46T Center Diff Gear: http://i7.photobucket.com/albums/y26...2-1201_IMG.jpg

The lesson for me in all of this is how important it is to inspect the truck thoroughly after a hard run. None of the problems above were noticeable while driving the truck. If I wouldn't have hit the pole and broke the a-arm I would've kept driving and I bet I would be replacing a lot more parts. This was also a good opportunity for me to completely disassemble the truck and clean it.

My outdrives (GS029) are kinda tore up also but I feel they are still serviceable. My front differential spewed all of it's gease inside the diff housing as well (the gasket failed (GS075) or the differential case (GS001) cracked somewhere). I think when I crack that diff open I may find more parts that need replacing. Unfortunately the four 3 * 10 screws used to bolt the diff together striped when I was trying to get them out. The other two diffs came apart without a problem. Anyone have any tips on getting these screws out? I may wait for a Nemesis differential to come up on eBay and score it.

I found that the servo saver was not adjusted correctly (I had about 4.5 mm of thread showing) where the manual specifies 6 mm and the 4 * 12 screws that secure the servo saver to the steering posts (GS019) were completely loose. These two things definitely contributed to my torque steering problem. Regardless, I switched the grease in the differentials to 10K in the front and 30K in the rear and center diff.

I also noted several errors in the CEN manual. Most notable was Step 29 on page 09. It says there is a 4mm locknut to secure the external shift unit on the main shaft. The design has been changed and now in place of the 4mm lock nut is a stub shaft that has a hole in the end of it. See the picture below of the stub shaft. I used a small allen wrench to put thru the hole and twist the stub shaft off. I called CEN and confirmed this. I should have asked for a part number for the stub shaft but I didn't (Maybe if CEN Racing reads this they could post the part number for this stub shaft). Other than that there are just some description errors. For instance Step 38 on Page 11 G73914 is listed as an 8*10*5 bearing when in fact G73914 is an 8*16*5 bearing. Small stuff for sure but it's all in the details.

Stub shaft on main shaft: http://i7.photobucket.com/albums/y26...2-1202_IMG.jpg

Stub shaft: http://i7.photobucket.com/albums/y26...2-1203_IMG.jpg

Overview of work area: http://i7.photobucket.com/albums/y26...2-1204_IMG.jpg

ouch thats a big parts list! $$

All in the price of being a noob I guess.