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RTXF1409B 9 speed trans problems. help!


dds92780

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Hey guys. My truck has 480k on it now. Its an r model and I like the mechanical engine but lately the trans has really been bothering me. For instance when I come to stop and I have to engage reverse there is always a loud popping sound once the clutch is released. It also does the sound when I let off the gas too quick. The rest of the transmission shifts fine but it doesn't shift like butter. it doesn't shift as fast as I would like it to. Every time I load it on a job site and I come to a stop and I have to back up it was made that popping sound so if I have to pull forward again it does this sound again if I have to go in reverse it does the sound again it's almost like the transmission doesn't like making the change from forward to reverse even though I'm at a complete stop.

This is been going on for a few months now and only seems to be getting a little worse even when I'm trying to drive and engage gears smoothly it's almost like the fifth wheel has play in it and if I don't push the pedal down gently it wants to jerk me a little bit I don't think it's related but it's just another thing I'm not liking about the whole transmission of the truck

I have taken it to my mechanic and all we've done so far is drained the transmission fluid and it came out clean I have talked to the owner of Christensen trucking and he says that the automatic power dividers go out sometimes and there are peanuts inside there that go bad and can cause the sound. I kind of agree with that but the sound clearly sounds gets coming from the front of the truck my next step was to take it to the mechanic and drain the power divider fluid and see if any metal shavings come out we have already checked all the U bolts and mounts and they are fine. the solution that my mechanic has is that I'm going to need a new transmission by the end of the year so my dilemma is do I put money into this truck and get a rebuilt 9 speed or do I put more money into it and get a 13 speed like I've always wanted that's built for the amount of torque that I'm making what all needs to be done to get a 13 speed into the trunk is it as simple as getting the 13 speed and lengthening the drive shaft?

My other thought was to move on and buy a nice 379 Peterbilt but I'm sure you guys would like me to stay around so help me stay in the Mack

Slow and Steady Wins the Race!

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By the way you describe it, it sounds like the troubles may be in the rear end and not the transmission. I had many of the same problems you have in a previous truck, and the gear in the front rear carrier had 2 broken teeth. Rear problems can move up the driveline and pretend to be a trans problem.

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Okay so I talked to my mechanic and we are going to drain bolt rear ends in the power divider to come up with an idea of what's going on and come up with a solution I tried to let the truck roll down a hill without using the clutch to get it into reverse and even though I managed to get it in gear while rolling as soon as I let off on the gas a little bit and makes the same popping sound.

Other than that the truck drives fine and the transmission shifts the way it should I just don't know what it could be at this point

Slow and Steady Wins the Race!

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drain rear ends and transmission, what type of rear ends you run? also the range syncro could be an issue. simply go from the cheapest way first all the way up to the costly one, you could also remove the shift bar housing of the tranny to inspect the main case to see if there are missing or broken teeth on the gears.

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also have you checked the slip yokes? you may have a splined yoke about to fail. have you went for a test drive with a mechanic? I would hook to a flat bed and have them lay on it and then see if they can see or hear any strange stuff, as mentioned before running the truck while on blocks can also help to trouble shoot the failed area.

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Got under the truck today with a guy that works for nagel trucking. We came to the. Conclusion that it needs a new carrier bearing. We accomplished this by leaving truck park and slowly releasing the clutch. The sound would violently come on.

Slow and Steady Wins the Race!

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