Discussion in 'Manual Transmission & Clutch' started by HotRodPC, Jul 9, 2012.
i have this exzact trans with a np 208 that came factory in my 84 k10
Runs and Drives? How do you like it for going out wheeling?
I had a new process A833 trans in a 71 Dodge Charger with the Hurst pistol grip shifter, 383 4bbl, many years ago. It was a badass transmission. Drove it hard all the time, never had a problem. It could burn rubber 1st through 3rd gear. I know the hemi/440 6 pack cars also used this trans but I think the input splines were different on the hemis but I cant remember the difference.
Yes, the input splines were very different as well as the length. The outputs were different too as well as the length of the tailhousings. About only thing similar is the slush box itself. Yep, they are strong transmissions. Allbeit, these for the GM trucks aren't quite as strong due to the small gear for the OD to make the OD ratio. You can probably beat on 1st and 2nd pretty good, which is where all the fun is at anyway, but I wouldn't be as hard on 3rd and Overdrive as I would one of the Dodge derived NP833's behind the Hemi's and 440's.
BTW, another tidbit about these these OD units, Dodge also used them in their D100-D150 trucks behind Crooked 6's and maybe 318's too. What many don't know about these with OD, not the standard Non OD 1-4 transmissions like in the old Dodge muscle cars, but only these with OD, 3rd and 4 gear position are actually reversed in the shift pattern. OD is where 3rd would be, and 3 is where 4th would. So you fake out the shifter by flipping the 3/4 shift lever on the outside of the case,opposite of the 1/2 and R shift lever. This way you get to keep your standard 1 - 4 H pattern at the shifter stick inside the vehicle. I thought that was very interesting. An ingenious design and thought by the guy who came up with it, rather than design and re-engineer a totally new transmission.
runs and drives every day .i just got this rig in april ....no idea what gear ratio`s are in the rear ends ....but it revs at 3 grand at about 110 kmh(75mph) off road it crawls along nicely in 4 low ...will crall upp over hills at idle ..and over stumps with ease (has a 4in lift with bf goodrich km 33`s)
Do you have a part number off of this HURST shifter for this GM transmission, the one I plan on gettin' don't have a shifter, may be a show stopper for me
I stumbled across one of these on Craigslist while looking for an NV3500 to put in my old Scout. Google led me here, and the information in this thread was so helpful that i registered to view the pics.
A little more digging turned this information up about how the OD was created in these transmissions and I thought it might be of interest. The below copy/paste was stolen from here: http://www.hotrodders.com/forum/interesting-4-speed-question-232864.html. Credit to user "Autogear" on the hotrodders forum.
ANY 4 speed with 4th being DIRECT DRIVE (ie 1:1) has the possibility of having this done.
Warner had a pre-production OD 4speed; Auto Gear made an M21 OD (no longer in production) for the Muncie, and New Process took the 833 and made the 833OD which is similar to the 'hemi' box but built for pick up trucks. Passon Performance is the place for these. Also; a NP 833 OD has a Hurst shifter from the factory. And; the 833OD was used in DODGE and GM pick up trucks.
Heres how its done:
The trans needs 1 gear to be Direct Drive that will become your 3rd gear
The actual OverDrive gear on the mainshaft is in the 3rd Gear position
This requires you to have a 2nd gear with the right ratio to bridge the 'gap' from 1st to direct drive (now 3rd). What youve done is essentially create a 3 speed with an overdrive 4th.
You flip your shift lever for 3/4 upside down and it will shift 1-2-4-3 in the trans and your standard H-pattern in the cab. Sneaky huh? We're good.
I dont have the NP833OD ratios handy; but heres what WE did several years ago for the M21OD (this is NO LONGER in production). 2.20 1st, 1.50 2nd, 1.00 3rd and 0.86 4th.
Now here's why WE don't produce it anymore:
Due to the constraints of the physical dimensions of the Muncie main case; you cant fit a 2.5x 1st gear in the case with the overdrive gear; so we're stuck with a mild OD for a 3.70-4.00+ rear gear. Due to the noise generated by running an oversize gear inside the main case, we had to run it on the tighter helix M20/21 platform. Your average gearhead can trip over a 400hp SB which is gonna stress this gearbox (even with the supercase and iron midplate) because you have really wide gear splits, a heavy gear in 3rd gear position, and the lighter duty M21 platform. Did I mention that gear is oversize? Its a royal pain in the butt to assemble it; you basically sneak the 3/4 slider over as far as you can and try to weasel the geartrain in and then you bump it and the struts and/or springs drop out. Also; because you require a special gear for 2nd speed, an oversized gear for the 3rd gear position and a new cluster gear...it requires new hobs (cutting equipment to make the gear), custom gears in a short run scenario (say 100 pieces) AND very finnicky attention to detail in making the OverDrive in order to minimize noise and vibration. My boss George bit the bullet and bought 200 complete sets from Antonio Masiero in Italy after doing all the design work himself.
Its a hard sell "you get a lighter duty (sub 400ft pounds manufacturers recommendation in most cases) 3speed with overdrive Muncie that doesn't have enough 1st gear to use with anything lower than a 3.55 in a light car" and when our complete M22Wide's were $2000; this was $2150 I believe. I never had one complaint from a customer; but the cost of doing this at Chrysler (New Process) or Warner in thousands of units, versus 1 guy on his drafting board for say 200 units every 5 years...LOL
Warner and NP did this during the first gas crunch back in the 70s as a quick fix to get people overdrive and sell V8 cars without tooling up for a 'modern' 5 speed. The first Borg Warner car 5speed was the T50 and it was used in things like the Vega. It was all torrington style bearings and had some really interesting design excercises (its endloaded like a T56 and was diecast). Doug Nash mingled T10 and Turbo Hydramatic parts and came up with the 4+3 in the Vette. It worked great but wasnt really designed for the Vette, it had something to do with GNs Camaros etc and the General insisted it go into the vette; several people had different ideas of how it needed to perform and Corporate politics really took the wind out of Doug's sails. BW also designed the T5 which is nothing T50 at all other than 5 speeds and from BW. The T5 is an outgrowth of the T4 4speed.
So there you have it; yes it can be done; pony up about 50grand and its easy LOL. It works and works well if you use quality parts, it'll be a flaming pile if you use Chi-com, Indian or Korean parts. Its very niche market and needs high volume to be feasible, and then you need to deal with the half-ton pick up truck ratios. Fine for cruisers, bad for performance enthusiasts.
Youre better off going with a 2.88 1st T10, or 2.98 (custom) Muncie 1st gear and a highway axle ratio like a 3.08. This gets you a traditional 4speed (no surgery required), a lightweight package (ours is 85 pounds) and a traditional price structure. Sorry for the long post
Skits bought my A833 for his Scout project. I'm sure he'll actually put it to use.
PLEASE @Skits start a build thread on the Scout in the Other Vehicles section! I love those things and I'm interested to see what you do with it
No doubt @Skits . You're welcome to start a build thread on GMSB. Just do it in the Other Vehicles section. Many of us build other projects other than just Squares. Those threads go here. http://www.gmsquarebody.com/forum/forumdisplay.php?f=15
If you're on a different Scout or Off-Road forum and doing it there, at least start a thread with some basic starter pics, then you can link to your build thread on the other forum.
Really late reply on this thread...I have a 73 GMC K25. It has the SM465 "4" speed, NP205, with 4.56 GM 14 bolt rear and Dana 44 front. I think the A833 would be a PERFECT addition to my truck so that it would be a little better driveable on the highway. Just wanted to say thanks for posting this thread.
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Hey guys, my truck has the 4.3/my6 combo. Had dual exhaust installed. Passenger side pipe is hitting the crossmember rattling pretty bad. Is the crossmember for a 4x4 or a v8 truck with this trans different than a 2wd? The crossmember is at an angle on passenger side (not meant for duals) on my 86 Scottsdale. The muffler man did not do a very good job installing the pipes so I really don't want to go back. I'm sure finding any kind of crossmember will be difficult to find but would like to know if a 4x4 or v8 crossmember will work. Thanks for any advice. Muley
Even if you do find a crossmember, it'll cost more than having the exhaust modified and I'd prefer myself to keep my truck as OEM as possible.
I also would not be afraid to go back to a guy who did a shitty job and at least give him the chance to make it right before I went and paid someone else to do it again before I trashed a guy for a shitty job. I don't walk on water and have been known to make a mistake or 2 myself. I try to never judge a guy by a mistake, but I will judge him on his efforts or lack thereof to make it right.
Just jumping in to share that I just picked up an '83 K10 with the NP/A833 4-speed. I found this thread after it gave me some trouble last night!
I put my plates on it right after work and planned to go for a drive...NOPE! It was stuck solidly in 1st gear! I searched around a while and found this thread (binge read all 19 pages) and another one on a Dodge Charger forum (http://dodgecharger.com/forum/index.php?topic=55483.0). Needless to say, 20 minutes later and it was back going!
I've still got to check fluid levels, and I think it needs a new input shaft bearing (same as throwout bearing or are there two different ones there?). It really wines in 1, 2, and a little in 4.
BTW, here's my truck...and subject of newfound obsession and destination of extra penny I can pick up!
I need to keep digging around to figure out the rest of the truck specs. Any recommendations for spots on this forum to easily ID the differentials by bolt pattern, etc.?
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