Dodge Cummins Diesel Forum banner

1 - 9 of 9 Posts

·
Registered
Joined
·
182 Posts
Discussion Starter #1
I know my truck feels the road vibration alot but when i'm on the go pedal and OD hits and then when LU hits I feel even more. Its not a steady shake but more of a increase in feeling the damn road vibration. Hard to explain but could the drop in RPM let me feel more of it or can there be a issue with my driveline? Seems to be mainly when im hard on the pedal
 

·
Registered
Joined
·
559 Posts
Just throwin in out there. D shaft center bearing or worn u joints
 

·
Registered
Joined
·
1,878 Posts
I have the same issue during lock up or at 40mph I get a wicked vibration. Im planning on replacing all U-joints in the near future as Im sure they are all original or close to it. Let me know what ya figure out.
 

·
Registered
Joined
·
1,675 Posts
Are you sure it's not converter lock up clutch shutter??? This is a very common problem especially when your on the go pedal. Simple check is to manually disconnect the LU converter at the speed you think it's doing it. If the vibration goes away, you have converter shutter. NOT Good & don't continue letting it do it

liteweight
 

·
Registered
Joined
·
32 Posts
It's the converter doods, too much power for the weak trans.... Especially at low rpm there's little line pressure when the motor makes the most torque.
Get a billet converter and a valve body. Goerend is awesome.
 

·
Registered
Joined
·
182 Posts
Discussion Starter #6
I have felt clutch shutter in my old rig, this isn't it. Its not driveline vibration, I have been thru the entire truck and cured everything I can.
I just put over 1000lbs in the box and the shake is still the same, the truck rides realy nice now though. Its like because the RPM drop in LU allows me to feel the road vibration more than when under load off the line.
Maybe I just worry to much and should just deal with the fact these trucks drive like tractors?
 

·
Registered
Joined
·
32 Posts
If it only happens in lock up in od.Anything more than an ez ,very ez, acceleration will make a stock converter shake. It just does, sorry but it's an expensive upgrade and even I didn't want to do it. I'm happy I did.
Belive what you want, this is a common issue.
Btw the more weight you put in it will increase the problem as the converter is flexing then slipping before power is transmitted to the wheels. A lighter weight truck won't run in to this issue as frequent.
Check your tps sensor, if it's out of spec it will pot the trans in od too early before there is enough line pressure. Tv cable adjustment could also affect these things but I suspect the tps if your truck goes to od before 45.
Search for the tps stuff it's all here.
The trans pump is making more line pressure at 45 but still not enough rpm for heavy acceleration to wot. Line pressure holds the converter tight... Not until 1600 or 1700 is there enough line pressure for wot.
The stock trans SUCKS even for a stock truck, even if it's new or rebuilt. It needs the beef! Your truck will thank you. I love feeling the torque down low instead of shaky truck...
At least consider a valve body and single billit torque converter and definitely check the tps, all you need is a multi meter and paper clip. Replacement tps is about 250 last time I checked.
Don't let this happen or you will be forced to correct the problem sooner than later. If you ruin your converter ,clutch friction material will get all up in the trans and soon the trans will need a rebuild. Not to mention if your truck fails to lock up the cooling circut will not engage and heat will continue to destroy the trans until it quits. We don't have trans temp on our trucks but even stock stock transmissions run the upper limit of acceptable operating temps.
Doood, I didn't see that you have a 3gsk and 10 plate, but the 3gsk changes the pedal/ fueling profile. Notice how you have to use less pedal for a response fron the truck? This correlates to the tps as well as line pressure relative to the amount of power the engine is making at a given rpm.
I had my 4gsk , fuel plate, and timing tools sitting in a box until I fixed up the tranny.....
I couldn't believe I paid more for the trans than i did for the whole truck! And I still plan on billet shafts later on,even then I'll sell the 47rh and do an Allison 1000 6speed. ( when I find a spare 10gs)

This gets pretty dam ridiculous. quick .

Why can't we just be happy with a 160 hp cool sounding truck....
 

·
Registered
Joined
·
1,675 Posts
I bought one of these when I first purchased my truck. It is a GREAT investment for converter shutter. Any time there is a call for the converter to be locked, wheather through the TPS or you manually lock it through a bypassed switch, this will pull the trans pressure to max pressure, even at part throttle.
Now, as far as your vibration, if your 100% sure it's NOT converter shutter due to previous experience, then you may have a couple bad engine mounts.


BD Power - Product: PressureLoc

liteweight
 

·
Registered
Joined
·
32 Posts
Those help to correct for throttle position .BUT you can't magically make the pump in the trans spin faster than it does at any given engine rpm ( other than unlocking the converter)

Pump speed/ engine rpm increases available line pressure, the vb just puts that pressure to work

That lil doodad just helps use what line pressure has built up there at a given rpm, and is like a band aid that will eventually fall off if you keep adding power.
But it's cheaper than a new trans...

If you let your truck shake , start saving money for tranny work or new walking shoes
 
1 - 9 of 9 Posts
Top