converting 9 speed in to 13 speed?

There are differences with the torque load around 200 Foot pounds between the converted 9-13 and the "Big 13"
Not a huge difference in the scheme of things.

Every mech I have ever talked to about the purchase of a rig in regards to tranny have all told me to check out the model# on the tranny, There are instances where the manufacturer has put in a converted 9-13 instead of the 13. They all told me to get truck with the "big 13". I don't know if that would have an effect on the resale value of a rig in regards to the trannys. Personally my next rig will have an 18......

 

Conv. 13spd are not that weak I have 1,018,000 on mine had 470,000 on when I got it that's when it was conv. And have hauled 70-80,000lbs and have had no problems with it at all.I run a 470 detroit and its @1650 with 2.93 rears, running all 48 states and canada pulls good runs good and get good mpg.
Other then putting on my PTO and taking it off and changing the fluid(synthetic) nothing has been done to the tranny and still has the org. clutch.

 

No one is saying they are weak.....
My concern is the resale value.....
That being said...every used truck will eventually have a buyer.....so in the big scheme of things.....doesn't matter if it works for you...

 

Ron are you possibly comparing the Super 13 #s to the convertible 9-13 #s?
There is another 13, not super, nor convertible, which is what I had in my '96 W900 behind a 3406E 475, Best of my memory, the model was a RTLO16913, which is rated the same as my present "convertible" 13, a RTLOC16913AT2

 

I guess every one would freak out if we started talking about changing a 13 speed over to an 18 speed? Vary simple change to do.
Back in the 70's Dad had a small 13 speed (compared to todays tranny's) with a turned up V12 Detriot and never had a problem.

If I could do it over I would speced my truck with 3,55 rears and a 13 speed doubleover. IMO the Acerts would pull better with this setup than the 13 speed, 3.36's and higher rears of todays trucks. Long legs never did run up hills very fast.
Just my 2 cents

 

Are you talking about a tranny swap, or changing the internals of a 13 in order to make it an 18?
If changing the internals is what you are referring to, could you direct me to where I might learn more about this?

 

Droy PM me sometime I will Give you a number in Houston. You can take an 18sp shift knob change the air lines and have an 18sp, but they say it want hold up long.(a few months) They sale a kit was $1100.00 to change it over. no one has ever gave me a good reason they want hold up. unless you need the lower 1st gear or in your case splitting the lower 5 with a tank their is no advantage to having an 18 the top gears are all the same

 

You have to change the shift knob and a slider bearing on a gear. Its the same gear that splits the top gears in a 13 speed. Unless your have a heavy load starting up hill its kinda pointless to have a 18 speed.

 

They're a "nice to have" in the Rockies driver....

 

True or pulling out of a rock pit.