92 300D - front axle shaking on acceleration
 

Hi,

1992 300D with 1987 om603 turbo.
My tie rods and idler arm bushing are bad and need replacement, waiting for parts but still have to drive the car.

Going 30-40mph and pressing throttle causes RPMs to go very high for a second before actually accelerating (there's audible transmission slam before acceleration).
Now I've noticed that, especially under load like going uphill, in addition to the above the front axle shakes as if the wheels were spinning in place...the shudder happens below 40mph, for example when moving from stop light and accelerating harder.

What could be the problem?
The reverse is slow (4 seconds) so I know tranny is worn out, but can it be something else as well? Low ATF?

Thanks

Of course check the ATF level, color and smell.

Concerning the Transmission My vehicle is older they yours and the symptoms were different. It was revving high before forward engagement but that was from a start.
I drained the ATF into a clean container (it seemed OK so I reused it), inspected what was in the pan and changed the AT Filter. It worked fine for about 1 year till my B-2 piston broke. Your later model should have the updated B-2 piston.

Would not hurt to check the Vacuum you connections for leaks (cracked rubber).

I'm not sure what you mean by "front axle"... please clarify.

Diesel911 is right about checking for vacuum leaks (and your atf level).

I found out myself recently, that you can't fully diagnose transmission/shifting problems if you haven't eliminated vacuum leaks as a culprit. I was getting shifts that almost felt like a rear-end collision they were so harsh. I was worried that my transmission was getting ready to die. I read through several threads here and discovered that if the vacuum signal to the transmission ain't right, the transmission will misbehave. Re-doing the vacuum lines and tees (and switching to a pressure activated waste gate, hence bypassing all of the "rats nest" on the passenger side of the engine compartment) cured all of the shifting issues on my '91 300D.

4 wheel drive? or front wheel bearing

You have 2 more or less separate problems, trans operation and vibration.

Failing transmissions generally don't shake unless the torque converter is breaking apart internally.

Be sure to look at the driveshaft rubber discs and center bearing / mount as this is a common failure point

No vacuum leaks, was low on ATF but filled it up. Second gear is flaring when going up to 3rd. Reverse is slipping (>4 seconds). It's ironic since I put a K1 spring kit 1000 miles ago and it didn't do anything.
I'll let my mechanic drive the car and then swap the transmission with 722.3 plus flex disc...