I noticed today that under heavy acceleration I can feel vibration from the rear. I’m not sure if it’s the tread on the tires or the drive shaft. Anyone else notice this?

When I’m just cruising or off throttle it’s as smooth as glass. I only notice it when I’m working on accelerating or hill climbing.

I noticed today that under heavy acceleration I can feel vibration from the rear. I’m not sure if it’s the tread on the tires or the drive shaft. Anyone else notice this?

When I’m just cruising or off throttle it’s as smooth as glass. I only notice it when I’m working on accelerating or hill climbing.

need some specs on the truck????

Just an 05 Dmax 4x4 with a Cognito 7-9 kit set at 7 and 35/12.50 toyo mt's on 20x9 wheels.

everything else is stock.

Driveline angle correct???

Just an 05 Dmax 4x4 with a Cognito 7-9 kit set at 7 and 35/12.50 toyo mt's on 20x9 wheels.

everything else is stock.

long bed or short bed? what lift is in the rear?

might just be axle wrap. may need some traction bars.

It's a short bed. I used the 5.5" blocks from cognito in the rear, they have some angle correction made into them. Also I have Bilstein 5100's front and rear.

Have you re-torqed your u-bolts?


Nor-Cal
Nick

Nope, planning to re-torque everything tomorrow night. I will check them when I get home tonight to make sure they arent lose though.

Hopefully it has nothing to do with the driveline angle because it’s already about as good as it can get with the pre-angled blocks.

Something else that’s odd is that if I go over 30 mph in 4 wheel drive the front CV’s make a lot of noise. Cognito said they sell upgraded CV’s if you want to go over 30 in FWD. Why is this? My CV angle is almost stock.

Think my driveshaft is doing something similar?

Still love the kit, just being picky.

Nope, planning to re-torque everything tomorrow night. I will check them when I get home tonight to make sure they arent lose though.

Hopefully it has nothing to do with the driveline angle because it’s already about as good as it can get with the pre-angled blocks.

Something else that’s odd is that if I go over 30 mph in 4 wheel drive the front CV’s make a lot of noise. Cognito said they sell upgraded CV’s if you want to go over 30 in FWD. Why is this? My CV angle is almost stock.
:confuzeld
What is all the mods you did to this truck?? Try making a signature with this info so people can help. You might be sitting to high and CV are binding??? A list of mods would help...

Make sure you include the color of your truck:D

Think my driveshaft is doing something similar?
U-bolts might be your problem.....keep us posted...

If you are doing alot of 4wd driving at higher speeds a front upgraded drive line is needed. A factory front drive line was not made to have heavy torq applied at higher speeds so you will have a vibration.



Still love the kit, just being picky.


Nor-Cal Nick

4x4 issue: i would almost bet money its the front driveshaft thats making funny vibe's not the cv's.

whats speeds are you getting vibrations at when accelerating?

get rid of those blocks first before anything

I had the same issue with mine. The taper on the block was too much. The yoke on the rear end should sit just below the line of the drive shaft to be correct. With the 5.5 tapered block it was up a little. I got some deaver springs for xmas and since I installed them I haven't had any problems at all. Smooth sailing. Blocks are bad. I would recommend the springs.

I knew the blocks were a bad idea - I'll try to order the deavers next month and see if that helps.

Will this bad driveline angle hurt anything?

I am having this same exact issue right now
just dropped the truck back off to have them look into it and do the 1000 mile re-torque.

everything seems to be pointing to needed deavers but i am trying to avoid it since that means i will have to do airbags also since i tow pretty heavy.

ill let you know if i hear anything different from them today

Just talked to the shop
there telling me my driveshaft is to short and it needs to be extended
since i have the 1 piece drive line apparently some times they are to short doesnt quit make sense that it would only be the case some times?

anyone had problem with this? or heard of this

like it says in my sig i only have it set at 7" with 5.5 blocks in the rear

I don't think the driveshaft is the problem. I also feel the same vibes under heavy acceleration and I have the blocks as well. I plan on upgrading to rear springs pretty soon.

I didnt think so either
so i took it to the driveshaft shop and had them double check
after describing my symtoms again to them they suggested 2-degree shims.

So then i drove it back to the lift shop but of course they dont have them in stock and i now have to come back again later after they order them.

:(

Is it a flat block currently?

With the 6" Deavers you will use the 2 degree shim anyways, so you are just preparing for the future.

Just talked to the shop
there telling me my driveshaft is to short and it needs to be extended
since i have the 1 piece drive line apparently some times they are to short doesnt quit make sense that it would only be the case some times?

anyone had problem with this? or heard of this

like it says in my sig i only have it set at 7" with 5.5 blocks in the rear

you need to talk to someone like Nick@ Nor-Cal or someone who knows these trucks like the back of their hand.