Transmission - Valve Body

[Star]

​

I was reading a few threads done a few years ago on 450 SEL 6.9 transmission valve bodies, and the question back then was does a standard 450 sel valve body work on a 6.9?
As last reported, I have transmission issues & my mechanic and I are going through the process of elimination.
If anyone in the TK forum knows the answer, I’d appreciate an up date

Starman

 

[Styria]

Hi Starman, whilst my responsive is probably no longer of any real value to you at this point of time, nevertheless it deserves an answer. There are four members of the 722.000 transmission family applicable to the 116 range. 90% of items are interchangeable, whilst the other 10% including the valve bodies, have only slight variations. There is a good chance that the 450 valve body can be interchanged, it is only the proper workshop manual that will illustrate the differences.
From my own observations over the years, valve bodies will give no troubles. Some mechanics (very well qualified) will not touch a valve body when rebuilding the transmission, but will merely soak them in petrol and pressure blow them with compressed air. Main problems with gearboxes relate to clutch lip seals, and friction plates. If you see this post, you may be able to fill us in with how you got on. Regards Styria

 

[sean sherry]

Yes Styria, only need to open a Valve Body if there is metal Filings from a Hard Part failure.
Then a major clean and polish of the Bores and Valves necessary, plus a check for warpage.
Later Electronic Controlled Transmissions can have a lot of Valve Body issues as the valves are on "Duty Cycle" and wear out the Bores... Boring Sleeve Kits are available from the USA to repair them.

 

[sean sherry]

Also........ I cut open all Torque Converters if the Transmission had metal filings.
All others I cleaned out with a Homemade Flusher. First drained by drilling an 1/8 th hole in the bottom and then welding up. Flushing the Heat Exchanger in the bottom of the Radiator was a waste of time. To many pockets for a filing to hide, would find its way to the Govenor Valve being flushed through by new Oil. A separate aftermarket Cooler solved this problem.

 

[Star]

Thanks for the replies, I’ve been overseas and only just returned.
At this stage, a full inspection of the gearbox by a well known local auto gearbox company, went over all vacuum lines, vacuum valve and all these items are ok, he removed the bottom off the gear box and then took out the valve body and found one very small piece of metal etc.
He then advised me that the gearbox needs to either pulled apart or replaced with another.
My thoughts we’re to have the valve body pulled apart and checked.
if that ends up being OK, I’ll remove the gearbox from the Gold 6.9 I purchased as spare ( Styria, it’s the 6.9 that you know well) get it checked over and install into my good 6.9

ill keep you all up to updated with my progress.

Merry Xmas everyone and let’s hope 2024 is a great year for all

 

[Michel]

Rather than start a new thread, I'm having flaring problems on my 380SE.
It takes off beautifully, but, get to 4th gear, unless you let it change up without acceleration, I get a high rev (flare).
Any idea what causes that, and is it easily fixable?

 

[sean sherry]

If transmission has acumulater Valves the spring is weak or broken If not a reseal or/and an O/H

 

[c107]

I assume you have checked fluid level, they are very sensitive to that.

 

[Styria]

Hi Michel, one could try and adjust the "THING" at the side of the gearbox - old age has caused me to forget its proper name - Sean will probably come to the rescue - but it will not always correct loss of clutch pressure on the change up to top gear without affecting all other gear changes. Many, many years ago I experienced that very same problem of flaring when changing from second to top gear. The remedy ? Remove the gearbox and replace the clutch lip seals. In my case with Gleaming Beauty, those seals were rock hard and obviously unable to maintain the proper oil pressure required.

Michel, hopefully I am wrong, so I'll keep my fingers crossed for you. BTW, some may suggest that you could add an additive - as a rule, they will not provide you with a solution. Regards Styria

If transmission has acumulater Valves the spring is weak or broken If not a reseal or/and an O/H

Sean, as you are aware, the two procedures are really about the same - removal and overhaul of gearbox - for a long term solution. Regards Styria

 

[sean sherry]

My money is on the hard clutch seals Old age

 

[Styria]

My money is on the hard clutch seals Old age

.....and I tend to agree. Regards Styria BTW, that "thingy" at the side - it's called the Modulator Valve. Regards Styria