Changing a 08 DD to a 09 DD?

[Skinner]

I thought I read on here that the case for a 08 DD and a 09 DD are the same. If that is the case can you put 09 gears into the 08 and lose the weight and turn it into a non-reverse DD case? then you could do the change and turn the motor backwards like the 09 and save some coin until you could get the DD lite.
lose all the servos and such. Just thinking! Thanks

 

[YooperScott]

Since the part number for the drive shaft appears the same then dimensionally the cases are likely the same. The spider (or whatever it's called) setup inside the DD is different because that's how the reverse happens, and because of that i'm sure is why the gears between reverse and non-reverse are different because the spacing is probably a little different on the small gear on the output side that engages in the spider. I think really the biggest part of the 6 or so pound weight difference between the two is the reverse solenoid which you could simply unbolt but leave the DD alone and leave the reverse arm there. To still have reverse you would have to get a new ECU though and they aren't cheap. Pretty sure the '08 oil pump isn't going to pump backwards but as long as it wouldn't hurt it and you only used reverse for getting off the trailer and stuff at low power and RPM I doubt the motor would even know about the lack of that tiny bit of oil. Oh yeah a helix with the reverse hotch to keep it from opening when going backwards too. The cost prohibitive part of the deal becomes the '09 ECU unless you know where to get them cheap.

 

[Ausm7499]

If its an 08 M1000 then the 09 reflash on your current ecu will give you the capability to run electronic reverse. There is a thread on this somewhere if you do some searching.

 

[YooperScott]

Oh yeah sorry I didn't even look at your sig. 1000 you can reflash and get the ability for reverse 800 you cannot.

 

[Skinner]

I want to get new gears so I was wondering if i could just get 09 gears(non reverse) and put the double bearing in?

 

[YooperScott]

HIGHLY doubt you can do that unless you used the '09 spider assembly too. My guess (after having changed the gears in my '08 M8 DD so i've looked inside but otherwise this is all just guessing) is the primary difference in the gears being reverse or not is the smaller gear on the output side that engages the spider assembly probably has a different spacing or something. Since dimensionally the case is likely the same from '08 to '09, as the driveshaft is the same, the differences I have to believe in mechanical reverse or not is all in the spider assembly. Also I really doubt cat would make the manufacturing change to the case when in '10 they didn't even bother to redo the rear tunnel for the old seat mounts you will notice if you look close (I think that's funny that the holes to mount the old seat are still there). Can you use the double bearing though, not sure? Perhaps someone that is much more intimately familiar can chime in but I really just have to believe that in '09 the hole for the mechanical reverse mechanism just wasn't machined out and the spider assembly is different otherwise they are gotta be pretty much the same. They seem to take the same bearings because the aftermarket kits don't have different ones for the different years. The '09s probably take more oil because there is less metal in the spider assembly that they are making up for to keep the level the same. So that amount of metal minus the 3 ounces of fluid plus the arm and solenoid are where the weight savings come from between the two.

 

[JHG]

Skinner-
The case is dimensionally the same, the insides are entirely different. The 09 gears won't fit in an 08 case. The planetary gear is different from 08 to 09. You can bolt in a take off case from an 09 but in order to convert your current case to an 09 style, you would have to replace everything inside and it would be more expensive than just buying an 09 case directly. You can buy a brand new 09 case complete with gears of your choice from Cat for about $600 and reuse you stock drive shaft. You can also order the complete case from Cat minus the gears for about $450 then put BDX gears in if you need the added strength. You won't have the weight loss of the BDX case but you will have the strength without the price of the BDX case.

 

[Skinner]

Skinner-
The case is dimensionally the same, the insides are entirely different. The 09 gears won't fit in an 08 case. The planetary gear is different from 08 to 09. You can bolt in a take off case from an 09 but in order to convert your current case to an 09 style, you would have to replace everything inside and it would be more expensive than just buying an 09 case directly. You can buy a brand new 09 case complete with gears of your choice from Cat for about $600 and reuse you stock drive shaft. You can also order the complete case from Cat minus the gears for about $450 then put BDX gears in if you need the added strength. You won't have the weight loss of the BDX case but you will have the strength without the price of the BDX case.

Dang. I might as well get the DD lite then.

Maybe I will do the electronic reverse and leave it alone this year and get the dd lite next year. I guess that it would be ok to run the stock dd backwards? Taped out this year. Thanks for the Info.