Drivetrain Shake when pulling

[pierceconsulting]

Hi Guys,
I just pulled my 13,000 lb trailer for the last two weeks, and when pulling from a stop I consistantly felt a shake from the drivetrain. This went away after everything got rolling. It almost felt like when you have a bad clutch. My truck is a 06' F350 Dually with 6.0 Powerstroke and the automatic tranny and a 4.10 posi rear end. I'm going to get it into my dealer, but thought I'd post it here to see if anyone might know what it might be. Other than this annoyance, the truck pulled like a champ in the 104 degree heat and I got 12-13 mpg at 65 mph.

[Rodslinger]

Welcome! Let me give this a bump.....

[harald@bd]

Think you have a trans issue,it probabley won't do it without the trailer so take it with you.They have had some trans issues in the past.

[pierceconsulting]

Thanks guys. Upon further research, it looks like the condition I'm seeing with my truck is called Launch Shudder. It looks like it's pretty common with the big pickups especially when towing and is related to the two piece driveshaft needing to be lubricated. Can anyone comment on this and did lubricating the driveshaft fix it?

[mschn99]

soory i missed this one man.....

it actually isnt lubrication, its driveline angle. there is a shim kit you can get from ford, but the gist is this.....

you can shimm it down more, which will stopp the shudder when you are towing.....

BUT its probably gonna make it do it when you are empty if you fix it so it doesnt do it towing........

Driveline angles are a very tricky thing, one or two degrees can make things shake pretty good......it is possible to hit the sweet spot, and if you put airbags on to keep the springs from dropping as much when you tow, that helps..........Marc

[pierceconsulting]

Hi Marc,

Thanks for the clarification....I sure do appreciate it. It sounds like I'll just live with it unless it get's worse. I tried a Timbren kit on the rear of the truck, but it made the ride so rough when towing that I had to take it back off again. Maybe I'll try the airbags instead.

Thanks again,
John

[03smokinstroker]

Had the same trouble . Look at driveshaft angles at the centerbearing when loaded & experiment with shimming down 1/4 inch at a time. I lifted my truck 4 inches & had to shim mine almost 2 inches. But even before the lift I took it to the dealer for the problem & they actually have a shim kit part # for this problem. An extra spring on the back will keep it from squatting & changing angle when under a load. Helped mine.

[gconsta]

I have the same problem you have. Everytime I start out while towing my 5th the truck goes through a small shuddering, sort of like a clutch chattering. Once rolling everythiong is fine. Glad to hear this is not abnormal.

[2006KR]

I'm just the opposite - not knowing the shift / torque convert lock up sequence when in tow/haul, it's sort of a guess, but if I had to guess, based on the following, I would have to think the torque converter clutch is my culprit:

Unloaded, especially when cold, all is well up thru 5th gear, then as soon as the torque converter lock, I get the shakes (well, the truck does anyway) which causes me to shake a bit.

Now loaded, when accelerating, it shifts great with no shakes up to 4th gear. As soon as the next shift? occurs, it starts to shake, so that is the reason for questioning the sequence .... does the torque convert lock before or after going into overdrive (5th gear) when in tow/haul.

My dealer has gone banana's over this - started with the engine, change the turbo and EGR valve, then the HPOP when south and was replaced. Still the shakes. Next, we went the transmission route, but still no luck. They want me to come in with the trailer, but ........

24' long truck, pulling a 37' 7Ton fifth wheel - almost 56' total in length, in madhouse xmas mall traffic, and not sure from the start that I can even get get the trailer into the lot, let alone back out between chain link fences, and where to I put the trailer if they figure it out? .....

I just may have to live with it until after the holidays the get really really brave and run it in.

[03smokinstroker]

The extra wieght of a load on the springs will change your driveline angles. Try shimming the center bearing. Ford has a shim kit. It will make it better. Mine is shimmed nearly 2 inches. I pull a 30 ft travel trailer with double slides & a golf cart in the back of the truck & had the same trouble. You don't need as much shimming as I did if you have factory springs & lift though.