2004 Yukon - Rumbling at ~50mph - Please help!!

[CO3_Yukon]

Hi - I have a 2004 Yukon with 101,000 miles. When I drive over 50 mph my car 'rumbles'. I will be driving on FLAT pavement and driving straight; yet, the car feels like you are going over bumps. It makes a rumbling noise. I have taken this to the dealership and they cannot find anything wrong. Dealership wasn't able to recreate the issue but that is because I am in NYC and they can't get up to 50mph+ because of traffic and dense area. Does anyone know what could be causing this? Any help would be greatly appreciated.

Thank you


Most parts are original; transmission REBUILT Oct' 23 (maybe a mistake to rebuild versus getting a full replacement?)

 

[strutaeng]

Probably needs to be put on a lift and ran to see if it's a drive line issue.

I know my 99 Silverado had a similar rumble/vibration (I could see the mirrors vibrate a little) when I went around 46 MPH. It wasn't a horrible vibration, but a little annoying. I want to say it did it since I bought it from the original owner back in 2008 and had like 88k on it.

I seem to recall it was related to the PWM TCC valve wearing out? I did eventually have the P1870 code until I swapped the transmission at 260k.

 

[CO3_Yukon]

I seem to recall it was related to the PWM TCC valve wearing out? I did eventually have the P18

Probably needs to be put on a lift and ran to see if it's a drive line issue.

I know my 99 Silverado had a similar rumble/vibration (I could see the mirrors vibrate a little) when I went around 46 MPH. It wasn't a horrible vibration, but a little annoying. I want to say it did it since I bought it from the original owner back in 2008 and had like 88k on it.

I seem to recall it was related to the PWM TCC valve wearing out? I did eventually have the P1870 code until I swapped the transmission at 260k.

@strutaeng I am googling this and the symptoms do seem to match the bad torque converter. Unfortunately it seems like maybe this could have been what contributed to having to replace my transmission at 95k miles and that the torque converter issue is hard to find and can go unnoticed. I will take to the dealership. Thank you so much for your help!

 

[strutaeng]

@strutaeng I am googling this and the symptoms do seem to match the bad torque converter. Unfortunately it seems like maybe this could have been what contributed to having to replace my transmission at 95k miles and that the torque converter issue is hard to find and can go unnoticed. I will take to the dealership. Thank you so much for your help!

I don't think its actually a bad torque converter. The TCC valve is in the transmission valve body and oscillates when the ECU commands it (as opposed to a "on-off" action). The oscillations wear the bore, which is an aluminum casting. There are aftermarket valve that rectify the issue. I really don't know the actual mechanism that causes the rumbling...

The forum is fortunate enough to have a transmission expert member. Maybe he can explain it better. But I'm pretty sure you need an advanced scanner that can command transmission controls manually to diagnose, so a shop is probably still your best bet.
@NickTransmissions please chime in.

 

[NickTransmissions]

Hi - I have a 2004 Yukon with 101,000 miles. When I drive over 50 mph my car 'rumbles'. I will be driving on FLAT pavement and driving straight; yet, the car feels like you are going over bumps. It makes a rumbling noise. I have taken this to the dealership and they cannot find anything wrong. Dealership wasn't able to recreate the issue but that is because I am in NYC and they can't get up to 50mph+ because of traffic and dense area. Does anyone know what could be causing this? Any help would be greatly appreciated.

Thank you


Most parts are original; transmission REBUILT Oct' 23 (maybe a mistake to rebuild versus getting a full replacement?)

Not sure why you'd think a transmission rebuilt by a competent shop would be any worse than a 'full replacement', especially considering the amount of hack reman companies out there.

Insofar as the problem itself, how long has this been happening? Was it occurring before the transmission was rebuilt back in 10.23?

Check for wheel balance issues especially if it's only happening at a certain speed or range of speeds. If torque converter was the problem you'd likely notice shuddering at speeds in excess of 30 mph but before 50 mph.

Scan the PCM for diagnostic trouble codes and post any here...Transmission codes start with P7XXX and go up numerically from there. Other things can be bad transmission rear mount, u-joints, wheel / hub bearings, etc so get underneath with a flashlight and flex mirror to see around tight spaces and do a good visual inspection.

 

[Blackcar]

If you have trailering button put in that mode and should not use lock up converter if I remember that way you might rule that out.

 

[CO3_Yukon]

@NickTransmissions the rumbling was NOT happening prior to the transmission rebuild in Oct '23. Following the transmission rebuild, I still have a 'sticky' shift from 1st to 2nd gear but transmission person looked at it again and couldn't seem to fix. In the last month, my car was leaking red fluid which seemed to be related to transmission and transmission person fixed. The rumbling/shuddering has been happening for 2-3 months. I did not mention this to the transmission guy because admittedly I didn't think it was related. I had separately gone to a dealership to inspect the 'rumbling/shuddering' issue and they didnt see anything wrong and could not recreate the issue (I think because they cannot get to higher speeds on streets around dealership). The rumbling/shuddering happens every time I drive the car over 40 mph. The rumbling/shuddering happens around 45-55 mph per the videos I have taken. Lastly, when the car is going under 15 mph it SOMETIMES, not always, makes weird mechanical noises that seem to come from the front part of the car. This issue happened last summer, stopped, then reocccured last weekend. I have no idea if all of these issues are related or not. I would attached a video of that noise but can't seem to attached a video.

@Blackcar I do have a trailer button so I suppose I could engage/turn on that button and then see if the rumbling/shuddering still occurs at 45-55 mph.


Thank you everyone!! I'm really at a loss here and I am thankful for your feedback!!

 

[NickTransmissions]

@NickTransmissions the rumbling was NOT happening prior to the transmission rebuild in Oct '23. Following the transmission rebuild, I still have a 'sticky' shift from 1st to 2nd gear but transmission person looked at it again and couldn't seem to fix. In the last month, my car was leaking red fluid which seemed to be related to transmission and transmission person fixed. The rumbling/shuddering has been happening for 2-3 months. I did not mention this to the transmission guy because admittedly I didn't think it was related. I had separately gone to a dealership to inspect the 'rumbling/shuddering' issue and they didnt see anything wrong and could not recreate the issue (I think because they cannot get to higher speeds on streets around dealership). The rumbling/shuddering happens every time I drive the car over 40 mph. The rumbling/shuddering happens around 45-55 mph per the videos I have taken. Lastly, when the car is going under 15 mph it SOMETIMES, not always, makes weird mechanical noises that seem to come from the front part of the car. This issue happened last summer, stopped, then reocccured last weekend. I have no idea if all of these issues are related or not. I would attached a video of that noise but can't seem to attached a video.

@Blackcar I do have a trailer button so I suppose I could engage/turn on that button and then see if the rumbling/shuddering still occurs at 45-55 mph.


Thank you everyone!! I'm really at a loss here and I am thankful for your feedback!!

If it's shuddering at/around 40mph then it could very well be converter....Was the converter replaced when the transmission was rebuilt.

Also, describe to me what you're referring to as a 'sticky' 1-2 shift - no clue what that means...Is it late and harsh or early/overly soft...Does the trans seem to 'hang' in 1st gear than slam into 2nd? Need a better description of this particular symptom.

You need to plug in a bi-directional scan tool and take it for a drive on the highway...Have all the transmission and torque converter data streams up on the screen. You will want to look at TCC slip speed and duty cycle. If the slip speed is in excess of 5-10 RPM when duty cycle is at 70% or so (and higher) then the TCC is slipping, trans/converter will have to come out and transmission may have to be gone through again...When converter clutches slip, they generate copious amounts of heat which rapidly degrades applied elements in the transmission (i.e. clutches and/or bands).

If you don't have such a scan tool, I will strongly suggest you invest in one...All too many DYIers dont have one...Don't rely on the dealership or anyone else for stuff you can easily do yourself...

 

[CO3_Yukon]

@NickTransmissions the shift from first to second gear is late and harsh; and yes, it does seem to hang in first gear and then slam into second. Once I get past second gear the shifting seems ok.
I wish I were a DIY'er but unfortunately I am not. I have been at a loss because after taking the car to the dealership they looked at the car twice and told me nothing was wrong (even though I have been disgruntled knowing that I still have these issues). I will need to share this feedback either with the guy who did the transmission replacement or go back to the dealership and try to be more specific with my issues. With my limited working knowledge of these issues I'm not sure that I am equipped to navigate the scanning tool, but I will do a search online for one and see if I can test it out!
Thanks again for your guidance here - you have been really helpful!!

 

[NickTransmissions]

@NickTransmissions the shift from first to second gear is late and harsh; and yes, it does seem to hang in first gear and then slam into second. Once I get past second gear the shifting seems ok.

Sounds like valve body, specifically TCC regulator valve. Can also be a broken outer 1-2 accumulator spring or worn 1-2 acc piston pin bore and/or seal, especially if you dont have a "component slipping" code. Lastly, could be worn 2-4 band combined with excessive band clearance.

@NickTransmissions
I wish I were a DIY'er but unfortunately I am not.

Why? No need to wish, just begin teaching yourself a thing or two here and there, build on your base of knowledge as you go...

@NickTransmissions I will need to share this feedback either with the guy who did the transmission replacement or go back to the dealership and try to be more specific with my issues.

Share the issues with your transmission builder to get his thoughts. See if he'd be willing to check out the transmission; it should still be under warranty if rebuilt in Oct of last year.

@NickTransmissions
Thanks again for your guidance here - you have been really helpful!!

You're welcome, man. Let us know what happens.