Transmission Opinions Needed

[dirtfarmer163]

I need y'all's help on choosing a tranmission. I have a 57 IH single axle that had a BD308 gas that i have replaced with a 5.9 cummins since the 2 engines had the same block size. The truck has a 6.88 rear that i can't find a faster gear set for, so i was thinkin of using a TRTL 720 or a TRQ 720.

So now for the questions

what bell housing to these trannys use and will i be able to bolt them to a 5.9???

how hard is it gonna be to find one????

are these tranys one piece like the duplex??

or is these a better more avalable tranny that finishes in the .6-.7 to 1 area???

Sorry guy i know its going in a IH but this is the only way i can think of to get some speed out of the lil truck, and i don't realy wanna mess with a short shaft between boxes. i will mainy be using it to pull gooseneck trailers and the most it will ever see is maybe 15000 pound on the deck. its just gonna be a play toy but i want it usable also.

thanx ahead of time for any info y'all can share matt

[Lmackattack]

If im not mistaken all the old mack twin stick boxes are married. at least all the popular boxes were. the mack trans would be fine but I think its a little over sized for the applacation you have?. also not sure if you would need all those gears that the quadbox has?

' what transmission is in the truck now? reason I ask is if it currently has a real slow first you may consider finding a diffrent axel assy with a faster road speed.

If your looking for road speed and cant find a diffrent diff ratio I would think a rear axel swap might be a little simpler job to do.

[dirtfarmer163]

the truck was a 5 speed direct with a 2 speed rear 6.88 high and 8.86 low. the reason im stayin with the original rear is 1 it has air brakes and 2 i can keep the original spoke wheels to match the front spokes and 3 finding a IH rear that light with air can be a challange. i have some IH rears at home with fast gears but none are fast enough and parts are not avalable. I agree i might not need all the gears of a quad but im after the .66:1 ratio and with all the gears i should be able to run in the 65mph range but a triplex would work

Edited February 14, 2010 by dirtfarmer163

[Lmackattack]

I have a double overdrive quad in my B model and If I recall its geared to run a max road speed of about 62-64MPH at a max engine rpm of 2100RPM. this is with a 5.73 rear end ratio. Will this new engine you have be able to run a Higher RPM. if not your max speed will never be higher than this. What you need to find out is what the lowest gear ratio was and see if the quad or 10 speed will match it for starting abilitys. If you want a trans with a little better parts avalibility the Mack T200 series has transmissions may intrest you. they have a .60 overdrive and come in a selection of diffrent forward speeds. the were good transmissions and most defects are known. such as the clutch pack issues for the range select.

[dirtfarmer163]

according to the road speed calculator 2500 rpm with 10.00r20 tires with 6.88 rear and .69 od comes out to 64.3 mph so that i can live with.

now the question lies, as to what bell housing is used and can i get what i need to bolt it to a 5.9 cummins

and what does it cost to buy a quad or a triplex

[Lmackattack]

Looks like 2500 RPM will meet the max speed your looking for but I dont like to run my engines at full RPM down the road unless I have to. I know they were built to do it but they are a little older now and the less stress the better IMHO. Regardless it will work for you .Lots of quads still around but in who knows what condition. I still have one for a spare but its been out doors for 8 years now. Im not sure of the bell housing size. Did you check on the clutch arangement. some of the macks had a push others had a pull style linkage..

[dirtfarmer163]

yes you are very right about running high rpm. its not gonna be an everyday driver just a play toy so im not to worryed about that. now if i can get a shaft size and the diameter of the bell i might be on to something

[Superdog]

You'll have to find a "baby quad" out of a B42.

[Rob]

I need y'all's help on choosing a tranmission. I have a 57 IH single axle that had a BD308 gas that i have replaced with a 5.9 cummins since the 2 engines had the same block size. The truck has a 6.88 rear that i can't find a faster gear set for, so i was thinkin of using a TRTL 720 or a TRQ 720.

So now for the questions

what bell housing to these trannys use and will i be able to bolt them to a 5.9???

how hard is it gonna be to find one????

are these tranys one piece like the duplex??

or is these a better more avalable tranny that finishes in the .6-.7 to 1 area???

Sorry guy i know its going in a IH but this is the only way i can think of to get some speed out of the lil truck, and i don't realy wanna mess with a short shaft between boxes. i will mainy be using it to pull gooseneck trailers and the most it will ever see is maybe 15000 pound on the deck. its just gonna be a play toy but i want it usable also.

thanx ahead of time for any info y'all can share matt

You're gonna have a tough time to fit a TR-72 series Mack trans behind that engine as all of them have an SAE #1 flywheel housing size. You mentioned that the BD-208 IH engine, and the 5.9 had the same "block size", (I assume you mean close physically) and the flywheel housing sizes are similar, (by assumption). I've had a couple of those gassers and they were an SAE #2 housing size which is much smaller than a TR-72 series by near a couple of inches, with less, and smaller capscrews for retention. You can obtain an SAE #1 flywheel housing for the engine but it will not be cheap, or readily available. The suggestion of replacing the rear axle is the most beneficial way to obtain what you propose to do. IH in the early days had spoke type wheels that were definately their own and wanting to retain them for the "look" is admirable but probably not feasible and be able to contain costs.

I would look at part numbers in drive axle service shops as there is a lot of information available and you may be able to swap your hubs onto a later axle assembly and have the best of all both worlds with a later axle and your old hubs.

If it were me I'd probably go with a 6+1 Spicer trans that was readily available in medium duty International trucks through the 90's. If possible I would get an iron cased one as the aluminum cases had some issues and if repaired corectly were no problems afterward. Plenty of gear reduction in that trans with overdrive too. This of course is my opinion but I had a couple and really liked them behind Dt-466 engines.

Rob

[dirtfarmer163]

superdog what model numbel is associated with the "baby quad" so i can begin my search for one. and would a triplex work or will i never find parts to mount it to the 5.9

thanks matt

[Superdog]

They were "77" series transmissions with the "770" being overdrive,several different ones.The one I have in my B46 is a called 14 speed and I have a B42 with a 20 speed.

[dirtfarmer163]

Rob first of all thanks

I have checked into that option and this is what i have found the spicer 6+1 and all the ones i have found are 1:1, is quite pricey used plus i would have to still get a rear. But now that we start talkin bell housing size the sae 2 was tight between the rails so i guess im back to square 1.

Now im gonna ask something yall may not know so here goes in the old trucks "IH FORD GM" that used big block V8s what size was the bell housing in those trucks???? im thinkin i could go with a pair of boxes made for those trucks and find the right combo to get the .6ish:1 ratio i need. didn't realy want the short shaft between boxes but if thats the way i gotta go what do ya do

just a thought

matt

[Rob]

Rob first of all thanks

I have checked into that option and this is what i have found the spicer 6+1 and all the ones i have found are 1:1, is quite pricey used plus i would have to still get a rear. But now that we start talkin bell housing size the sae 2 was tight between the rails so i guess im back to square 1.

Now im gonna ask something yall may not know so here goes in the old trucks "IH FORD GM" that used big block V8s what size was the bell housing in those trucks???? im thinkin i could go with a pair of boxes made for those trucks and find the right combo to get the .6ish:1 ratio i need. didn't realy want the short shaft between boxes but if thats the way i gotta go what do ya do

just a thought

matt

Both of the 6+1 Spicer transmissions I had were overdrive. I ordered them both new, but don't recall it being a problem or anything special.

Most of the large block gas engines produced by Ford, GM, Chrysler and such had integral flywheel housing mounts cast into the block like a car does. This was however not always the case. Many of the same engines were supplied with corporate to SAE adapters to allow for other transmission installations such as Fuller, Spicer, etc. using the SAE bolt up pattern. I don't know about input shafts to these transmissions, and clutch discs used in the applications as they could be different that the common setup as this would be sort of an adaptation and not really standard issue.

Rob

[dirtfarmer163]

looks as if i might be S.O.L. till i get home. dad has a old ford with a V8 and 5+3 that is a tri axle dump i might have to study that and make some calls to the boys at cresson ridge and see what i can piece together to get the ratios i need but thanks to every one for your help

If y'all have any other ideas let me know thanks matt