# 4450 trans



## bighamp (Dec 2, 2012)

I have a 4450 with the 15 sp powershift. It does great in even numbered gears but seems to be slipping in numbered gears. It is especially noticeable in 13th and 15th gear. It is full of fluid and does great as long as it is in even numbered ones. Anyone have this problem before or have any idea what it may be? Thanks


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## clive (Mar 1, 2012)

Is it in every even gear it slips or just some? I can look at my book but need a bit more info first


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## MBTRAC (May 28, 2012)

It's been quite a while since we've owned/operated a 4450, they're a great row crop machine & hold up well against comparisons with modern gear.

Starting with the simple stuff first:-
1. Does the problem get progressively worse with constant use?
2. Rather than investigating pressures/valving/springs/clutches - Have you changed the 2x trasmission filters & oil lately & then this problem has started ? Either way, I'd be draining the oil & saving, checking the filters/oil for contamination & if all clean refilling with the same oil, then determine if they's any improvement....I recall a cavitation/air lock problem post servicing we had on another model JD Powrshift which produced slippage issues on between two gear sets changes

At a guess "worse case", with issues 12-15gears (&/or 1-3? ???) I'd say it's most likely to be a problem in the front clutch pack, it's common for the sealing rings on the shaft progressively to wear out & stops the operating pressure being achieved on the clutch pack - also usually the friction discs need replacement & depending if its been on the way out for a while sometimes consequential damage to a hub/shaft.
Can also be only a oring/packing in the clutch pack or a shift valve but you'll need to run through diagnositcs with a set of gauges to determine.
On the positive side the C1/front clutch pack should be accessible without taking the cab off.


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