VOLVO VNL 670 VIBRATION HELP

I have 2011 Volvo VNL 670 w cummins isx 15in it. I have this vibration actually i don’t know how to describe it drives me crazy. I always feel this vibration in the seat or under the truck but steering wheel steady not shaking, so i think is driveline issue. Replaced shocks all over, new front springs, new tires all over, new brakes drums and shoes, new carrier bearing, driveline doesn’t have any movement at the joints. New fuel pump. What can be . I tried to check if its the motor mounts like someone else explain in other post he said let of the cluch slowly and watch the engine for movements, but i cant see any movement maybe a lil but i guess that is normal. Now started when i shift to 6th gear and accelate i can feel the vibration and in 7th less vibration is just weird and when im driving it feels more like shaking then vibrating. Help please. Low on budget need to find cheap solution if possible. Thanks

 

Ride heigh is 8 1/2 in front airbags and 8 3/4 rears.

 

Yes, i had another post i don’t know if its me or everyone but this vibrations are killing my vibe to drive. Like literally i’m driving and i think something will break down.

I can imagine 40mph 400miles that was probably long journey, but maybe two years ago i think i replaced mine power diver on the front diff. That clunk also between the tranny and the engine i think its been there since forever( i drive this truck for 5 years).

There is no movement in the u joints but the truck has 970000 miles with rebuild engine in it and has 150000miles on it.

today i was driving and i was loaded 45k water from columbus, OH to Vandalia, OH and the truck was fine not that much vibration. The load that i pick it is 17k and i feel the vibration. The vibration that was happening in 6th gear when acceleratin today was gone neither 7 or 8, but few times when i was driving back today around 65mph because my truck is locked on 65mph it started grrrrrrr vibratin and stop after 5-10 sec then happend again after few miles. I also found some oil under the tranny behind.
i don’t know what to say i can write a book easy.

 

Oil is leaking where is the yellow line but under not where the yellow line is.

 

Carrier bearing is replaced and checked is good. The vibration i think is there when i’m empty or light loaded, but when heave like 40k i barely feel it.