Bad vibrations m1008 except at idle.

[maxpanic]

So I just took the m1008 out for an extended drive (1.5 hours) and about half way through the trip the truck suddenly started vibrating. Seems that it stops vibrating on idle and vibrates a lot at 25-35 mph whether accelerating or decelerating. Starts vibrating around 5 or 10 mph. It used to vibrate pretty bad around 45-50mph but now it seems to be throughout the speed range.

What do ya'll think?

Thanks in advance for the help. you guys always seem to know how to fix these things really well.

 

[doghead]

Look at your harmonic balancer, with it idling and with it shut off.

 

[Cucvnut]

Death wobbled ?

 

[mistaken1]

My money is on doghead but I am wondering if a motor mount would exhibit the same symptoms.

 

[ranchhopper]

Bad trans-TC mount nothing holding the rear steady had it happen to me.

 

[rnd-motorsports]

Slowly rev it above idle while in park if vibe is not there you know to look in drive line and not engine check drive shafts shafts, u joints a tire gone bad . Jack up rear end put on a good pair jack stands and block front wheels put in drive and and have somebody take it up till you get the vibe then look at things my money will be on a tire gone bad cord pulled or separating! let us know!

 

[maxpanic]

I will be checking it out on Tuesday afternoon. I will get back to you guys on the results of the tests you guys have suggested Tuesday or Wednesday.

Thanks again for the help.

How would I determine if it is "Death Wobbled"?

 

[doghead]

Did you feel any wobble in the steering wheel? Was the truck shaking side to side like you were out of control? That's death wobble.

or, did you simply feel vibration through-out the truck.

 

[maxpanic]

I see, no death wobble then. Just vibrations throughout the truck.

 

[pmramsey]

No one has mentioned this but check the oil. If it is low or the oil pump is failing, there will not always be sufficient oil to run the lifters and the timing will be off.

 

[ixpacman]

Three weeks ago started up my 1008 and headed to work .got to the bank and noticed a vibration in addition to strange noise. Got my banking done and headed out.I was in a little of a huryy so I was cruising pretty fast (55 mph) all of a sudden vibration increased then the alternator light went on. Before I had a chance to process all this data engine stopped. Immediately !! Coasted to a stop and realized that I just blew the engine. I got this truck almost straight from the military at 59,000 miles. It now had 73,000 miles on it but I have been anal about oil changes and maintanence.I have always used Amsoil HD 15w40 diesel and had made many medium range trips. Motor has always been solid and dependable so this was a mystery to me. I have never blown a motor in anything that I have owned for a signifcant time so I was determined to find out why this happened. A friend fortunately had a military 6.2 J motor for short money so I tore the motor out immediately. Couldn't turn crankshaft to get flywheel bolts off so I pulled oil pan and started pulling rods and mains. Every bearing was mint. no metal in pan but block was demolished and crankshaft was broken into three seperate pieces. One of the pieces almost hit me in the head when I got the rod bearings unbolted. Finally got crank off and sure as *&*^% thye harmonic balancer had sheered the key off the front of crank even though the bolt wasnt noticeably loose. Needless to say I bought brand new balancer and key for new motor ,but any 6.2 diesels I have in the future will have a thorough inspection of the balancer key and related parts so that might be something you might want to at least check. Love this site and hope this adds positive advice

 

[maxpanic]

Well, looks like its the bracket between the the transmission and t-case. Anyone know of the best source for a replacement part? Can it be welded?

 

[maxpanic]

Oh, yeah. And the process for replacement. How involved is it? I figure I take out the t-case and remove the bracket and any gaskets I see?

 

[rnd-motorsports]

Yes in most cases it can be welded hard to say for sure without seeing how or were its cracked or broke. to replace use a jack and put a short piece of 2x4 ,4x4 or something under trany pan, remove mount bolts and raise trans and transfer a little remove the bolts in the frame on both sides and remove cross member. any 3/4 or 1 ton with a 400 trans and 4x4 should be the same or have yours fixed

 

[mistaken1]

Bad trans-TC mount nothing holding the rear steady had it happen to me.

You called it.

 

[maxpanic]

I am kind of surprised. I can't find a parts supplier that has this adaptor anywhere. I am going to try the local auto wreckers this Saturday but i thought it should be available from Napa, Autozone, Checker and non of them have it neither does 6 states distributers or transmission exchange or advanced adaptors. I am puzzled as to why I am having such a hard time finding this part. Any advice of obtaining this part would be appreciated.

 

[maxpanic]

Also, the m1008 has a th400 and np208, right?

 

[pmramsey]

Maybe...sometime it may be np205

 

[Cucvnut]

its a M1008 it has a208 most likely

 

[Cucvnut]

I have a T case mount for a 241 it will work you just need a diff cross member i have that also.