'01 6speed 2nd gear vibration @1500rpms

[rrexcavate]

Just bought a 6speed Dually 4x4 this week and noticed that 2nd gear has a vibration at 1500 rpms. Installed a gooseneck ball and pulled 15,000lbs and discovered that there is something seriously wrong with 2nd gear. . vibration became very bad when towing a load. Any ideas? All other gears and rpms are fine.

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[MidwestMotorman]

Sorry to hear of your troubles. Did you happen to notice what speed you were at? Did you try first gear,at a higher rpm, at that same speed? If it is driveshaft or tire related it will be at that same speed. Being it is a 4x4, it could be related to front end as well.
Check your rear tire pressures. A dually is sensitive to that, but tire problems are usually more apparent at higher speeds.
One other thing, check the torque of the rear lugs nuts. I have seen them come loose and cause all kinds of vibration.
If your can't track it down, have a dealership pull the plug and check the trans for metal shavings. You will probably have to have a new trans. The dealership will check tire balance and go through all sorts of things before they put in a trans.
Good luck, and I hope you get a loaner.

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99 2500 QC longbox, SLT, 4x4, 24V Cummins, 5 spd, 3. 55 LSD

 

[MidwestMotorman]

You could also try lifting the rear of the truck and spin the tires to check for an out-of-round tire or rim. If I remember right, second gear is about 8-20mph. You would feel the out-of-round condition then before the highway speed smooths it out some.

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99 2500 QC longbox, SLT, 4x4, 24V Cummins, 5 spd, 3. 55 LSD

 

[rrexcavate]

Update:
Dodge Dealer test drove the truck today and says that the height of the truck being 4x4 and all puts the driveline is such an angle that they sometimes have to put a shim kit on. So, they have ordered the shim kit and will install and I will update you all. Thanks for all your suggestions.

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2001 4x4 Quad 3500 6speed 3. 54, overloads, camper special, tow package, dark garnet and more!

 

[MidwestMotorman]

Hope that helps, but loading the truck normally turns the pinion up and relieves the stress of the driveline. If it gets worse loaded, then it probably is not the angle.
Best of luck.

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99 2500 QC longbox, SLT, 4x4, 24V Cummins, 5 spd, 3. 55 LSD

 

[Waltz]

Had a similar problem when starting out in 2nd gear. Started day I picked up the truck from the dealer. Took it back repeatedly without satisfaction. Finally went to another dealer who found that there was a DC - TSB issued a few years ago recommending installing shim packs changing rear driveline to carrier bearing angle. Had the shims installed and is AOK now. Dealer found that the driveline angle was off approx. 3 degrees from DC specs. Good luck

 

[rhoads]

Let's think about this ,vib's in second and not 1-4-5-6- it has nothing to do with angle- tires . If so it d would Also be through other gears!!!!!

 

[MidwestMotorman]

Again, more info is needed on the problem. I believe Ford uses the same trans, and a call to a bigger dealership, Dodge or Ford, could net some info.
We call all speculate on what it is, but is the problem just at 1500rpm in second, or is it through the whole rpm band in second? Does the problem show up in 4Lo as well as 4Hi or 2Hi? The trans would turn the same rpms in 4Lo and the vibration would be the same. If it is different, look elsewhere.

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99 2500 QC longbox, SLT, 4x4, 24V Cummins, 5 spd, 3. 55 LSD

[This message has been edited by nathanbush (edited 05-27-2001). ]

 

[rrexcavate]

The vibration is only in 2nd gear. It last from 1500rpms to 1800rpms. Whether you are pulling a load or not. It is worse with a load. Have not tried 4Lo. . but will and update you.

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www.rrexcavate.com 2001 & 1999 4x4 Quad 3500 6speed 3. 54, overloads, camper special, tow package, PacBrake, TST Power Max II

 

[MidwestMotorman]

The best thing to do is out the transfer case in neutral, and then put the trans in second gear. If there is any vibration in the transmission, you will feel it without any truck movement to interfere.

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99 2500 QC longbox, SLT, 4x4, 24V Cummins, 5 spd, 3. 55 LSD

 

[rrexcavate]

Nathan, There is no vibration in 2nd gear while the transfer case is in Neutral.

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www.rrexcavate.com 2001 & 1999 4x4 Quad 3500 6speed 3. 54, overloads, camper special, tow package, PacBrake, TST Power Max II

 

[MidwestMotorman]

Do you take off in second gear? I am wondering if this is caused by an injector, or another component, that is not working properly at that 1500-1800 rpm. Second gear would have quite a pull on the motor compared to the other gears and the mph/rpm loads encountered.

Try jumping from first to third while moving to see if the load in third causes an engine "shudder" in that rpm range.

I am not a certified mechanic, but hopefully the dodge techs can get this firured out. I am just trying to think of some solutions to narrow things down.

In my 99, the turbo really does not crank up until about 1800rpm, so the engine would kind of rely upon injection and aspiration below that. Unless your vibration is engine lugging/lurching due to lack of fuel or air? Mine used to lurch at 1300 before I got a programming upgrade from dodge. I am lurch free from 700 on up.

Anyway, I hope this post was not too long, but eventually this will be figured out be someone.



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99 2500 QC longbox, SLT, 4x4, 24V Cummins, 5 spd, 3. 55 LSD

 

[rrexcavate]

Latest Update:

Took my truck to Dodge Dealer and they installed a SHIM Kit on the rear end where it attaches to the leaf springs. I hopped in and took off in the truck and 2nd gear still vibrates but not as bad. The dealership is going to take the truck tomorrow and work on it the next couple of days. The vibration is still worse when towing a load and most evident in 2nd gear between 1500 and 1800 rpms.