4907 trans to a 4909 chassis

[holeyguy66]

well while breaking in my new engine i noticed a clunking noise when rolling. pulled the tranny off and apart to find some gears ate up. my question is. will a tranny for a 4907-4908 fit a 4909 chassis

[ScottRogers]

I have a 4909 that wont shift to 2nd gear and have researched this. The tranny will physically fit but there is a difference in the size of the output shaft. On the 4909 tranny the output shaft steps down to 5mm on the ends where the drive shafts connect and the 4907/4908 tranny stays at 6mm. There are 2 ways that I know to address this, one is to change the output shaft in the tranny. two is to change out the yokes on the end of the driveshafts in your truck to the larger 4907/4908 style.

[holeyguy66]

thats pretty good info. i got one coming and by the time im done fixin all the old parts its gonna be new again. but i scratched the head on my brand new 21 tm today

[Wildman4910]

The 4908/07 trany is exactly the same as the 4909 except for the output shaft & brake hex/disc.

You will need to put FOC #5195 in the 4908/07 trany to make it a direct drop in replacement for your 4909 trany.
http://buy.traxxas.com/product_info....854ld47eimc7v0

[holeyguy66]

The 4908/07 trany is exactly the same as the 4909 except for the output shaft & brake hex/disc.

You will need to put FOC #5195 in the 4908/07 trany to make it a direct drop in replacement for your 4909 trany.
http://buy.traxxas.com/product_info....854ld47eimc7v0

why would i need the foc for my chassis. i know dumb question

[kuskye25]

because the output shaft is the only difference, and thatll give you the correct mm output shafts for your 4909 transmission yokes to hook up to your 4909 shafts

[kuskye25]

also you can replace the weak 3 shoe slipper pads on the spur slipper with a 2.5 maxx brake disk, as i wound up doing...

[kuskye25]

just for reference and good info here is my build where i modded a 4909 steel geared trans and e-maxx diffs into my 4910...

http://traxxas.com/forums/showthread...-vs.-2.5-diffs

[kuskye25]

end result though just for clarification you have a 4907 trans already but all the output shaft stuff is what makes yours a 4909, basically just fix whats broke in yours, and add the FOC to delete reverse and all its pesky issues if you dont like reverse...

[holeyguy66]

well 34 bux for a complete tranny was what go me i got the 4907 output yolks already here ill just mate my u-joints to them and hopefully it will work if not. well im a minitrucker and what do we do if it dont fit? we customize it to fit

[Wildman4910]

You will find the 4908/07 output shaft is longer due to the pin style brakes vs. the hex style your 4909 has, if you have the tools you can just cut down the shaft & redrill it for your 4909 brake setup.

[holeyguy66]

i got a set of 4907 output yolks here and the tranny came in today. im thinking of mating my shafts to the newer yolks i dont see a prob with that but i just got this truck out of storage so im kinda relearning this thing. also if i cant do said mod then cant i just pull my output shafts out of the original tranny and swap them or do i need to buy the foc kit. to me kinda pointless when the new one has only forward

[Wildman4910]

The problem you are going run into is the 4909 chassis is shorter in the front of the trany.
The 4907 pin brake stick out farther then the 4909 hex brake, right where the rear throttle servo mount is.

Is your 4909 trany w/reverse or does it have a FOC?

Below you can see the difference in the 2 chassis, the pin style brake sticks out right into the rear servo mount area.
4909 chassis



4908/07 chassis

[holeyguy66]

my old trans still had the opti drive till i updated to the 2.4 system but yes it has reverse. i just went ahead and ordered the foc kit you showed me. turns out was way to long lol. i know stubborn but hey its fun learning this truck more and more

[Wildman4910]

my old trans still had the opti drive till i updated to the 2.4 system but yes it has reverse. i just went ahead and ordered the foc kit you showed me. turns out was way to long lol. i know stubborn but hey its fun learning this truck more and more

Stubborn is something my wife accuses me of at least once a day!

So I know where your coming from.

We all start at square one when new to the hobby, the longer you keep at it the more you pick up.

[holeyguy66]

Stubborn is something my wife accuses me of at least once a day!

So I know where your coming from.

We all start at square one when new to the hobby, the longer you keep at it the more you pick up.

yea i have fun making stuff work. i just didnt wanna spend the money on the foc kit for my chassis since all i needed was the output shaft. the 4907 tranny is forward only anyways. but its raining here and isnt suppoed to let up till the middle of next week so theres plenty of time to modify and fix stuff.

[Wildman4910]

Can't argue there, I made my own shock stand~offs instead of spending the $14 on the longer ones I needed.

[holeyguy66]

well its bright and sunny now. so i stand corrected. but is it simple to install the out put shaft. and do i need to use supplied gears since my new trans is forward only

[Wildman4910]

well its bright and sunny now. so i stand corrected. but is it simple to install the out put shaft. and do i need to use supplied gears since my new trans is forward only

All you need to swap out is the output shaft, long 4907 FOC out & drop in the new shorter 4909 FOC.

Just put the leftover gears in you parts box as only the shaft it's self is shorter, keep the gears for spares.

[holeyguy66]

All you need to swap out is the output shaft, long 4907 FOC out & drop in the new shorter 4909 FOC.

Just put the leftover gears in you parts box as only the shaft it's self is shorter, keep the gears for spares.

sweet thanks for the info