722.6 just about to fit 4th since april 07

[alancee]

i would welcome your views on this sad saga,jan 13 07 wrote off my 165k w210 with a 722.5 gearbox and broke both legs,whilst awaiting injuries to heal bought a e240 avantgarde v6 ,2.6 with 180k,722.6 gearbox tiptronic ,full history plenty stamps ex chauffer car from winchester,mb in winchester and southampton did all the services,car looks a cracker and i was not worried on the miles,been driving mb for 20yrs with no problems,when i could drive ok again i go 20 miles gearbox failure,stop start stop start then lift it to my works 40miles away,asume gearbox dead locate used 722.6 with converter at £900,buy it fit ,ok ,3 months samething and out of dismantlers warrenty,in the deep end again,sent original box and tq to poland for refurbish,got message back the original gear box had a broken shaft in ,i did not doubt that because it made a heck of a noise stopping,so locate another box ,this time a c200 engine and box,only need the box ,get ready to change it and find its a 97 with a tq drain screw,still electronic but it has a plunger at the rear for the park i presume,strip sump disable that lock by cutting the shaft and remove debris,no muck ,i am a fully qualified precision engineer with my own workshop,also had to change the bellhousing as they are different and the torque converter back to number 2 gearbox ,c200 tq is smaller than e240 one,so fingers crossed that the older electronic pre tiptronic box works with the tip gearshift between the seats,yes it does ,so you can fit pre tips to tip changers ,the gearbox worked in all modes ,kick ,double kick ,cruise ,speed limiter,and all tiptronic moves,all lights came up and i thought that was it,10 days ago for christmas it happened again,no drive,i am really disapionted and want to know if i am wrong ,mb wrong,or what,i have another box to fit in but i would really like some help here please,i just do not want ,will not be put in a dealers workshop for this ,i want to figure it myself ,underline i am about to fit my 4th 722.6 gearbox since april 07 !!, any help ,what am i missing,and i cannot find any torque converters for thew210 yr 2000 november to change ,but i dont think its the tq but what do i know,not enough i suppose,regards to you all ,please help if you can,alancee

 

[type49]

Don't bother on the horses or lottery, you don't seem to have any luck! I pressume you are completely flushing the rad/cooler & pipes before each change. Is your oil somehow being contaminated by your rad, there was a problem with Valeo radiators but your car shouldn't be effected, although it's still possible. Also, I've been told but not comfirmed myself, the clutch plates & brake bands are slightly different for 4, 6, & 8 cylinder engines due to their torque increases. Could it be your C200 box was just ripped apart by your V6 engine??

 

[alancee]

hi type 49,all things are possible ,thats what i want suggestions,flushing ,no i didnt but all that would have been left could not have been much anyway after it was all drained,converter out of car on the floor etc,there was no evidence of any water /coolant in the box,did not get a chemical check though,as far as the box being ripped apart well i use it to go to work basically motorway at 80 max and no quick gettaways etc so it was used sparingly if you like i am wrong side of 52,no smells or anything either ,gearbox not me,ps on the water oil mix wouldnt the oil be pushed into the water due to the pressure as the water is not that higher pressure,thanks ,keep them coming please ,alancee

 

[Uncle Benz]

It seems that on the mercs, the water always passes into the gearbox. This is the opposite to many others, like VW, that commonly exhibit cooler faults.

As I read your commentary, you reused a torque converter from a gearbox that had failed, as well as a potentially contaminated oil cooler. I would sadly fear that this may be the root of your trouble. I have learned this lesson by bitter experience in the past, and flushing is no guarantee either. New coolers and pipes all the way for me...

 

[television]

Just to give an idea of how many different boxes there are in the 722.6 range



722.600/601/604/605/606/607/608/609/611/614/616/617/618/629/634/639/660/661/662/664/665/666//661/662/664/665/689/695/699/996.

 

[type49]

Are you sure you havn't missed one

 

[alancee]

thanks for your replies yes there are a lot of 722.6 boxes ,each different in a small way ,could be bell housing ,drive dog hole pitch to propshaft ,but what i need is constructive thoughts like the contamination theory,if i pressure test the pipes and cooler with 30/40 lbs and its ok what then?i have read in a long long thread about the contamination and it was said its on a particular make of rad and mine is not one of those ,is it? mb put part numbers on things for their benifit and pocket and also to confuse people that want to fix it them selves ,alot of those gearbox part numbers i bet even mb dont know the differance,stiil hunting the lead to the answer,alancee

 

[alancee]

the last box on the list should rear 722.696 not 966 because thats my original box i told you about back when it all started,thanks alancee

 

[television]

the last box on the list should rear 722.696 not 966 because thats my original box i told you about back when it all started,thanks alancee

Thank you (eagle eyes) I will amend my list, do not overlook the possibility that Type 49 pointed out

 

[television]

Are you sure you havn't missed one

Nope, but I got one wrong, so I am awaiting my marching orders

 

[alancee]

i would really like to hear what the member in pompey thinks ,is it black cat?
alancee

 

[alancee]

sorry blackc55 is the name ,i got it wrong,alancee

 

[television]

sorry blackc55 is the name ,i got it wrong,alancee

He may well post in the morning,,,Type49 is a good MB techie

 

[alancee]

still here and hoping for a direction to go,please,

 

[dieselman]

I'd go with the 200 box not being strong enough. Each box has a torque loading specification and the 200 is the lowest.

Surely you can obtain the correct box, there's plenty of 240's around.

 

[Xtractorfan]

I get the feeling here that a lot of these boxes u have been using have already had their 8 lives lived and some into their ninth, in fact now all of them, I dont think that u could rip apart one of these boxes unless u were rallying or serious towing constantly. they are fairly bullet proof. and I must add u really are glutton for punishment or u like work. as u are an engineer why not transpant a complete unit. engine n box from a known good motor ..low miles etc and ensure proper alignment of propshaft and rear axle and use the donor vehicle mounts as well..another thing is the cooling system working properly (Gearbox)

 

[alancee]

I get the feeling here that a lot of these boxes u have been using have already had their 8 lives lived and some into their ninth, in fact now all of them, I dont think that u could rip apart one of these boxes unless u were rallying or serious towing constantly. they are fairly bullet proof. and I must add u really are glutton for punishment or u like work. as u are an engineer why not transpant a complete unit. engine n box from a known good motor ..low miles etc and ensure proper alignment of propshaft and rear axle and use the donor vehicle mounts as well..another thing is the cooling system working properly (Gearbox)

like the input,i could agree partly with the first point on expected life ,but how do you abuse an auto box,its virtually idiot proof as far i can see ,put me right please anyone really ,i want to get to the root problem,bullet proof i dont think so,that means me ,i dont,i think they are totally unreliable,i think they are enough to put me off buying another mercedes ever after 20 years

 

[alancee]

continued,which to me is a great shame,yesterday i even went to look at a 124 series 2 door coupe ,it did not hit the buttons,its not going too after using modern technoligy that works ,but the stuff that does not work costs so much to put right,if i put out so much wrong stuff i would not be in business today,by the way this week is 23 years in manufacturing engineering,hands on,as for finding engine box doing transplant ,well ive said iy ,i am an engineer,hands on,not a wealthy man ,just try to use my head,no deep pockets,cheap charlie if you like,thanks ,please keep ideas coming ,its a gear box ,thats all