transmission fitment

[mudtoy1]

Hi there,

first post and I've gotta say that this site is AWESOME! Seems like a great group of knowledgeable people. have learned so much already. Just bought a 1981 I/C 8x8 argo and I've had a few trips out and what a blast!

I've had a few mishaps already and most of them I have been able to remedy myself except this transmission issue. when I put it in reverse, it just pops the lever to the right a bit and grinds and won't actually go in reverse. I have another transmission that I can put in but not sure if it is the same. the ser # on it is 4929H. anyone happen to know if that is the same and if it will drop right in or have a idea on how to fix my current one?

Thanks so much in advance for any info!

[ARGOJIM]

mudtoy1, the trans should be able to drop in as the mounts are the same however without seeing pics of both trans. it's hard to say if it will drop right in, you didn't mention the serial of the current trans.. The older trans. will all bolt in place but there were some changes to the mold for the different brake systems, also the letter denotes the gear ratio.

In the manual section of the site is the service manual with a trans. section, could be the reverse idler gear has chipped teeth and/or a worn bushing, the bushing is easily replaced and the gear is flippable. If the double gear is chipped it's more money. I'd suggest tearing it down using the manual as a guide, or if trans look identical and the spare is known good you could swap it out.

[Rock Doctor]

Have you tried running it in Reverse without the Firewall installed?
Reason:
I've had to "open" the slot in a couple Argo Firewalls to allow the shifter to be fully pushed to the left. Sometimes the Firewall interfiers with the shifter, keeping it from being fully shifted over, or it can flex and push the shifter towards Neutral.
Just something to check/try, before you tear the Trans out.

RD

[mudtoy1]

Thanks for the replies guys! I'm pretty sure that it is in the transmission because with the old trans out of the machine, I've tried holding the selector in reverse and turning the clutch by hand and it still try's to move the shifter to the right and you can feel the grinding in the case as if it's not fully engaged. well that sounds like good news that it might be as simple as a bushing or just flipping the gear over. I will take a look through that manual and see what i can come up with as far as taking it apart. Any tips as to not have everything fall apart when I go to split the case or does everything stay put? I'm great at taking things apart, putting it back together is a different story haha. thanks again

[mudtoy1]

also can someone tell me what the model number of the trans that is in my argo stock so I can find the above manual that ARGOJIM is talking about or maybe even provide a link? thanks again!

[ARGOJIM]

RD is correct on the firewall deal but that mostly happens with the pop out firewall models, one other thing to check when you have it apart is the shift fork for slop and or straightness. if your sticks are low mounted your housings should have no bosses for the calipers to mount to which I believe the h trans to have, If your sticks are high mounted and both trans have the bosses on them they should interchange easily.

The trans. model is 34-100, for any needed parts you'll need the serial number on the case as some internals differ and gear ratio's change gear counts, follow the manuals instructions, when splitting the case be sure to tap on the output shaft on the cover side ( best to have 3 hands with this).

[mudtoy1]

excellent!! thanks for the help and identifying the trans for me! much appreciated ARGOJIM. Hopefully i will be able to get back to this project before the long wknd comes along. cheers.

[spookum]

The biggest obstical you have is the breaks. Are they hydraulic or manual? In an 81 I assume that they are manual. A more modern trans should have spots to bolt up a hydraulic break calipers.... But your manual breaks should be fine.

[mudtoy1]

my brakes are actually hydraulic in the machine at the moment. The spare trans i have is equipped with manual brakes at the moment.

[spookum]

Hopefully it has bungs drilled in the trans to transfer the calipers over...

[ARGOJIM]

Spookum, the 81 I/C should have the calipers mounted to the powerpack frame.