Recently acquired 91 300TE 4matic with 91K miles. Rebuilt MB transfer case @ 80K miles. When making U-turns or small radius turns, it feels like front or rear is 'binding' up... like right and left side are not turning independently as they should. Also, when accelerating or just before coming to a stop under braking there is a series of subtle jerks coming from drivetrain.
No warning lites are illuminated on the dash and NO codes were pulled.
Also, when the lever is put in 'test' mode, car drives smoothly. All the issues go away. All fluids in trans, transfer case, and hydraulic were recently replaced and are at proper levels. No leaks.
Is this a sensor problem or something mechanical in the differentials?

The last time I saw an issue like this, it came out to be the previous owner had the car towed on a hook type truck.
The repair cost was several thousands of US dollars, at the MB dealer.

All four tires must be the same height, tire pressure, size. Any lights on the dash ,ABS,ASD warning,ASD function. I work on one, years ago, it had a bad steering angle sensor. The 4matics have a very complicated system , I guess you know that already.

Good luck.

Tire size "already stated" is VERY critical...but since the lamp is on & no codes that means a hydraulic problem...You need so start by having the system bled.

ALSO have the fluid level checked in the transfer case...if it is high then CHANGE that fluid(ATF.. separate fill) & have the hydraulic system to the transfer case bled..

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M.B. Doc-
The hydraulic fluid was just changed and is at proper levels. I also had the fluid in the transfer case also replaced. Hydraulic fluid shows proper level in the bottle.
Could the mechanic have messed up with the transfer case fluid.
P.S. I mentioned that when I move the lever in to 'TEST MODE', the car drives like a dream. I was under the impression that that rules out a hydraulic problem..... but again, I am just parrotting what I've read in many threads on this site.
Any further thoughts? Thanks

With scanner do you get code 1 which means NO faults OR do you get no codes as you first stated...

IF no code appears then the problem is Hydraulic...again bleeding the transfer case & activating the solenoid for the differential & then bleeding it IS the correct starting point...of course the engine MUST be running to bleed that system & there are bleeder at both places.

Ask your tech if the transfer case was too full...that is the most common leakage point for that system...Fluid should NOT come out of the fill plug..but be level with that plug.

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator

HELP!! Can anyone out there provide instructions on how to bleed my 1991300TE 4matic system. I recently acquired the vehicle with very low mileage, 38,400, so it is obvious it has been setting in a garage most of it's life. Vehicle is cherry but I would like to get 4matic squared away before winter in Anchorage, ALaska. I have been trained as a mechanic so have good basic understanding of systems...just don't have the procedures to follow. Is it really difficult or can a person with a little better than average mechanical ability get it done? Thanks...

One thing you might consider...when the car is first starting up the 4Matic is always automatically engaged. this means that if you are just starting up and turning a tight corner, as you probably will be doing in a "U" turn, the 4Matic has all wheels engaged. Once you are over the 12mph or so speed, and there is no road condition requiring it, the 4Matic system shuts down. As you state, when the system is in "test mode", which is essentially turned off, you do not feel this condition.

SRHarvey,

Sorry I posted here by mistake

Thanks

Roger