6420 transmission choices

[3020jd2955]

Looking at a couple of used 6420s. One has the basic 16 speed powerquad, which I am familiar with. Another has a 24 speed transmission. I haven't seen the tractor yet, but would this be a 24 speed powerquad or is it the autoquad transmission? If it is autoquad are there any issues with this transmission? If it is the regular powerquad with just a couple added ranges, were there any issues with those over the 16 speed? Both tractors are less than 3k hours.

Also, if overall condition and quality was similiar, would the extra money for a 6420 over a 6400/6410 really worth it? Tractor will just be a hay/chore/feeding tractor.

 

[PeterE]

It could be either a 24-speed PowrQuad or an AutoQuad. Both were available.

 

[richardinnz]

The 24 speed box is an option box added to the range box. 16 speeders have ranges A thru D, 24 speeders have ranges A thru F. You get extra speeds in the working ranges. Reliable unit, nothing to worry about there.
The 6020 series Deeres went through a lot of changes, you may have 16 or 8 valve motor, Stanadyne DE10, Bosch VPE44 or Denso HPCR fuel system depending on how old and SE or standard. SE tractors have a lot less electronics
The Engine ECU on ROPS tractors is in a horrible place on the 6020s and we have had a number of failures. They can have ZF or Deere (Spicer) front axles, both are really good units. 68** and above in all series get a much beefier USA built rear end, may be designated 73** in the US, we got the 68** and 69** we had to order 72** & 73** from the US instead of Germany to get a bar instead of flange rear axles, no difference in reliability.
I would prefer a 6000 or 6010 series, tranny basicly the same but simplfied engine, less electronics. Try to steer away from the 'wedding cake' rockshaft control on the 6000 series, but a lot have been converted to the 'mouse' control as they failed which is a lot more reliable, but expensive to retrofit if it has not been done already.
A major problem we had with the 6020 series is the wiring harnes rubbing out around the left rear cab pillar between the side and rear window.