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Transmission problem ??

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skull791

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got a tmax classic with 3.3 in it that I got use. I got everything running. One specific thing that is killing me is this weird jerk or hick up that the car is doing. when the rpm goes litle higher. the trans ingages and make the car jump/hiccup forward. if I lower my idle the the car stop running. I know is not my clutch that is engaging. I'm pretty sure that that is something to do with my trans. This is so fry ken annoying. some times it dose every few min then some times it dose it every few seconds. can't even try to tune the car when it dose it. It just jerks hard forward. I don't think that that's how it should be. Anyone????? before I call traxess
 
It HAS to be the clutch bell. Power doesn't even get to the transmision if cluch bell is working properly and your idle is low enough.

When the rpm raises it engages the clutch at the bell and delivers power to the transmision.

If raising idle makes car move forward.... and lowering idle makes car stall... retune from factory specs or check your clutch behind the bell.
 
knall said:
It HAS to be the clutch bell. Power doesn't even get to the transmision if cluch bell is working properly and your idle is low enough.

When the rpm raises it engages the clutch at the bell and delivers power to the transmision.

If raising idle makes car move forward.... and lowering idle makes car stall... retune from factory specs or check your clutch behind the bell.
Click to expand...

well I took the bell of and it looks like the surface inside got 2 groves. exactly in the places that the clutch will grab. I will get new bell and see.
 
If it's an older maxx (black trans case and large spur), then it more than likely has reverse. There's a clutch mechanism in there that causes it to jump. Although, you should be able to get your idle low enough to keep it from jumping like that. If you can't, then either your tune needs adjusted or your clutch shoes/bearings may need some attention.

Personally, if it does have reverse, I'd ditch it and get the FOC (forward only conversion). This removes reverse and other junk out of the trans, but also removes the constant lurching. Makes the truck much more responsive off the line as well.

I believe this is the FOC for the older maxx:
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXCNA8&P=7
 
olds97_lss said:
If it's an older maxx (black trans case and large spur), then it more than likely has reverse. There's a clutch mechanism in there that causes it to jump. Although, you should be able to get your idle low enough to keep it from jumping like that. If you can't, then either your tune needs adjusted or your clutch shoes/bearings may need some attention.

Personally, if it does have reverse, I'd ditch it and get the FOC (forward only conversion). This removes reverse and other junk out of the trans, but also removes the constant lurching. Makes the truck much more responsive off the line as well.

I believe this is the FOC for the older maxx:
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXCNA8&P=7
Click to expand...


thank you that's the answer I was looking for. someone who knows. I knew it has to be in a that older trans. Now do new tmax trans do the same or is it improve. My truck is 2.5r with 3.3 motor in it and it dose have reverse. Can I install new gray trans in it. is it possible also would it help with the jumping. In the beginning I did like the reverse but now with all this jumping is just pissing me off. I will like to save it but if I can't then I think I will get it remove. let me know if there is better newer tmax trans that will fit in there that will let me keep reverse.
 
Make sure your clutch spring isn't broken. they will run fine with a broken spring but it will jump around at idle like you're talking about.
 
drdoom405 said:
Make sure your clutch spring isn't broken. they will run fine with a broken spring but it will jump around at idle like you're talking about.
Click to expand...

yes I know check that already and I did replace clutch bell housing, clutch and spring. Still dose it. I know if you have reverse they do this but they should not do it as much when idling. That car dose it like is on drugs just jumps all over the place. I was wondering if there is anything in my trans that could be worn out over years and dose it more that it should. Is there any parts that control that in my trans ??
 
skull791 said:
thank you that's the answer I was looking for. someone who knows. I knew it has to be in a that older trans. Now do new tmax trans do the same or is it improve. My truck is 2.5r with 3.3 motor in it and it dose have reverse. Can I install new gray trans in it. is it possible also would it help with the jumping. In the beginning I did like the reverse but now with all this jumping is just pissing me off. I will like to save it but if I can't then I think I will get it remove. let me know if there is better newer tmax trans that will fit in there that will let me keep reverse.
Click to expand...

Yes, I had the s-maxx version of the t-maxx.. which was a 2wd, forward only setup. I smoked the trans with the black casing.. and then chose to go for the opti-drive transmission with forward and reverse. any maxx series transmission will fit your truck. If you decide to go that route, I found mine on ebay. I don't recall what I paid for it.. but you can probably find one fully assembled on there and just swap them out in the truck. It was well worth it to me.:first_place:
 
SteelCityNitro said:
Yes, I had the s-maxx version of the t-maxx.. which was a 2wd, forward only setup. I smoked the trans with the black casing.. and then chose to go for the opti-drive transmission with forward and reverse. any maxx series transmission will fit your truck. If you decide to go that route, I found mine on ebay. I don't recall what I paid for it.. but you can probably find one fully assembled on there and just swap them out in the truck. It was well worth it to me.:first_place:
Click to expand...

cool now dose anyone knows if revo transmission with opti is the same. Found one cheap on ebay.
 
skull791 said:
cool now dose anyone knows if revo transmission with opti is the same. Found one cheap on ebay.
Click to expand...

i looked it up, and the case looks shorter than that if a maxx transmission.. i would go with a maxx one just to be on the safe side.. i forgot to mention before.. if you opt for an opti drive transmission.. you will have to get the opti-drive module and a receiver box that it will fit inside.
 
SteelCityNitro said:
i looked it up, and the case looks shorter than that if a maxx transmission.. i would go with a maxx one just to be on the safe side.. i forgot to mention before.. if you opt for an opti drive transmission.. you will have to get the opti-drive module and a receiver box that it will fit inside.
Click to expand...

how is opti drive. I hear mix things about it. is is smoth and how dose it shift ? How much did you pay for yours? are they black or gray case ?
 
Opti-drive is not a very good system which is why Traxxas ditched it. I would find you one of the FOC for yours and be done with it. The only problem with the grey case tranny with the older T-Maxx is the brake set up is different and it takes some modding to get it to work correctly. I did it on mine so it can be done...just with a bit of work and fabricating.
 
if u get the newest tranny it wont fit without some modding they got the diff brake setup but the old 3.3 grey tranny will drop right in
 

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