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Posted

I've got a 07 4x4 with 150k. Just started having transmission trouble. Believe it's a 4L60E. There are 2 different things going on.

First issue is that it doesn't shift out of first every now and then... once every 2 weeks or so. When this happens the speedometer doesn't register and stays at zero. Pull over and stop, put it in park, then back into drive and it's fine.

Second issue is in reverse. If I put it in reverse and go light on the gas, or not at all, it works fine. If I give it more gas, it locks up and sounds like a butter knife in bike spokes. No control over the speed of the "clicking", just have to let it slow to a stop on its own. I'm guessing the torque converter is going. Here's a link to a Ring video of it doing it when trying to back into my garage: 

https://ring.com/share/d28e2c3d-fc5d-42cc-ac9b-bcb6ae2ea8b3

Any help would be appreciated

Posted

Neither of those are torque converter problems.

 

On 2/13/2024 at 10:20 PM, cr1hotrod said:

First issue is that it doesn't shift out of first every now and then... once every 2 weeks or so. When this happens the speedometer doesn't register and stays at zero. Pull over and stop, put it in park, then back into drive and it's fine.

I'm inclined to think this is an electrical speed sensor signal issue (dead speedometer, the truck doesn't think its moving so no need to shift...), but going back to park then to drive wouldn't resolve that. 

 

On 2/13/2024 at 10:20 PM, cr1hotrod said:

Second issue is in reverse. If I put it in reverse and go light on the gas, or not at all, it works fine. If I give it more gas, it locks up and sounds like a butter knife in bike spokes. No control over the speed of the "clicking", just have to let it slow to a stop on its own.

Mechanical issue, probably rebuild time.

 

Fluid condition?

 

For fun, what happens if you turn on tow/haul mode when these conditions are present?

 

What happens if you manually shift the truck to 2 when its stuck in 1?

  • 3 weeks later...
Posted

Upon further testing....

 

When it's stuck in first, doesn't matter if I shift manually. Still stuck in first and speedo stays at zero. Have to stop and put it into park, then works fine. Very random, took a few weeks for it to do it again... Hense the late response.

 

You think the reverse issue couldn't be torque converter? To me it sounds like internal fins slipping or contracting something....or something like that. Especially since it works until a certain pressure, then it starts clicking and loses ability to move. But, I work for Freightliner, I know very little about these small transmissions.

Posted
On 3/5/2024 at 1:07 PM, cr1hotrod said:

You think the reverse issue couldn't be torque converter?

 

Especially since it works until a certain pressure, then it starts clicking and loses ability to move.

If it were the torque converter it would behave the same forwards or backwards.

 

The lack of a speed signal that coincides with being stuck in first is interesting to me, additionally how shifting to park resolves it. My initial thought remains that the speed signal issue is causing the lack of shift from first. 

Posted

I see what you're talking about with the tc... Just dawned on me that it's always spinning the same direction...duh. I'm wondering if I might have a transfer case issue. Speed sensor is located in there and I wonder if it's not all the way in 2wd or something like that. Both problems started at the same time. But that wouldn't explain the falling out of reverse.... Just rambling on now

Anyway, thanks for discussing it, I think I might have breakdown and take it somewhere

Posted

Try changing the fluid on the transfer case - not as a fix, but to inspect fluid condition. Looking for too much metal in the fluid and while you're there inspect the speed sensor.

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