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diesel: which tranny/gears to go with?

muddybuddy

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hey there, im planning on my next rig being a diesel k30. ive read alot of stuff about the pros and cons to various trannys and such on here, and i guess my gear question goes along with it. im assuming it comes with a th400, but i kinda like the idea of overdrive or maybe a 4spd, i dont know,what are my options? i need your help! also what about gears? i wanna run 35x14.50s. i have 35s on my current truck with od and was gonna swap in 5.13s on that. would 5.13s be too much for a diesel and 35s or would it just be bad a$$? i dont want this thing to be gutless both on the road and off. its going to be my dd, but im hoping that the diesel will help me out in mpgs. i dont really do any highway driving cept occasional 200mile trip couple times a year.

for 35s on a diesel which tranny and gear combo would you chose and why?
 
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5.13's, 700R-4 and 35's would be great. 2250 rpm at 65 mph, which should net you close to 20 mpg. It'll also have a fair amount of grunt and do well off road.

Without overdrive, using a TH400 or SM 465 I'd lean towards 4.10's with that tire size...and expect a little less fuel economy. You'd be turning ~2500-2600 rpm at 65 with either of those trannies.

Rene
 
is there anything thats stronger than the 700r4? im kinda scared of them. a friend (protechk5) has gone through 4 700r4s and i dont wanna deal with that. what about a 4L80 or something? i only wanna have to swap trannys one time.

also, i want something that will bolt up nicely with a np205. seems like theres alot of work required with a 700r4/205 combo

thanks
 
tRustyK5 said:
5.13's, 700R-4 and 35's would be great. 2250 rpm at 65 mph, which should net you close to 20 mpg. It'll also have a fair amount of grunt and do well off road.

Without overdrive, using a TH400 or SM 465 I'd lean towards 4.10's with that tire size...and expect a little less fuel economy. You'd be turning ~2500-2600 rpm at 65 with either of those trannies.

Rene

lol I was thinking almost exactly the same rene! :waytogo:
 
muddybuddy said:
is there anything thats stronger than the 700r4? im kinda scared of them. a friend (protechk5) has gone through 4 700r4s and i dont wanna deal with that. what about a 4L80 or something? i only wanna have to swap trannys one time.

also, i want something that will bolt up nicely with a np205. seems like theres alot of work required with a 700r4/205 combo

thanks

honestly bro, for what you want I think an SM465/NP205 combo is the best way to go with maybe 4.10's for more power or 3.73's for more economy... ;)
 
muddybuddy said:
is there anything thats stronger than the 700r4? im kinda scared of them. a friend (protechk5) has gone through 4 700r4s and i dont wanna deal with that. what about a 4L80 or something? i only wanna have to swap trannys one time.

also, i want something that will bolt up nicely with a np205. seems like theres alot of work required with a 700r4/205 combo

thanks

Well the turbo 400 in my truck bolts up to my 205 real nice lol I got the tranny back from being rebuilt and its now back in my truck.. she truck gets down the road a lot better now.. shifts firm and sweet I just took some more pics of the CUCV but I dont think I have your email..
 
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Rene has the right idea with the 6.2L & SM465. :waytogo:

I have a 6.2L/TH400... IMO the 6.2L is not powerful enough to run with a TH400 unless you have really short gearing. Don't plan on any better than 12-15mpg either.

I'd go with a TH700 if I *had* to have an auto. The OD, lockup, lower mass, and better 1st gear ratio all help in the economy department.

My own preference is for the simplicity and efficiency of a manual trans. :D
 
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