Do gearboxes break?

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rupert's
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Do gearboxes break?

Post by rupert's » October 13th, 2020, 6:25 pm

Hi everyone! I could use your opinion on gearboxes.

I have to buy one for the A2 and I don't know whether to buy it new, reconditioned or used, the last one would be without having done anything ... as is.

I think I have read somewhere that these gearboxes break with some ease .... is this so? Is it true that mutt gearboxes are soft?

Do you know which piece usually breaks?
If you buy a used one ... Do you advise changing a component as a prevention?

Maybe what tends to break is one of these images and if I buy a used one, should I change the parts before using it?

Greetings to all and thanks for your opinions!
Attachments
kit caja de camios 2.png
kit caja de cambios.jpg

199th mp
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Re: Do gearboxes break?

Post by 199th mp » October 13th, 2020, 6:51 pm

while many other owners have more experience than i do, i will tell you what the transmission shop told me when they replaced all of the seals and gaskets in my gear box. they told me it was very sturdy, and reminded them of a tractor gearbox. straight cut gears, very heavy duty for the size of the vehicle. mine never gave me a bit of trouble for the years i owned it, and i drove it all over the place, even on the freeway in california. once the oil leaks were fixed, it was solid as a rock.

rickf
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Re: Do gearboxes break?

Post by rickf » October 13th, 2020, 8:52 pm

These transmissions are seriously over engineered for the vehicle. I have never seen one "break". I have seen them damaged by abuse, lack of oil from leaks and that type of thing but as far as breaking no, they don't break. The main issue with them is the reverse lockout detent spring gets weak and they will grind going into third gear if you try to shift it like a newer car. That is a simple fix if you can find the repair kit.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

svramselaar
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Re: Do gearboxes break?

Post by svramselaar » October 15th, 2020, 7:30 am

hi
you want to buy a gearbox
do you have aproblem with yours ?
you can repair it yourself with a bit help from the g838
i can send you a pm with a drawing for the tools you need to make them yourself
and a sort of manual how to do it

george

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Re: Do gearboxes break?

Post by rupert's » October 15th, 2020, 5:53 pm

rickf wrote:
October 13th, 2020, 8:52 pm
These transmissions are seriously over engineered for the vehicle. I have never seen one "break". I have seen them damaged by abuse, lack of oil from leaks and that type of thing but as far as breaking no, they don't break. The main issue with them is the reverse lockout detent spring gets weak and they will grind going into third gear if you try to shift it like a newer car. That is a simple fix if you can find the repair kit.

Ok, as I understand from your answers the gearboxes are strong, (not as I thought) if there is no danger of breakage, do not change anything for prevention ... regarding the repair that you tell me ... I do not understand, I have never repaired a gearbox, I have the one of my a2 broken, now I can upload an image, but it is broken and I don't think I have a solution.
My concern is if to buy a second hand gearbox I have to change something to prevent a bad future.
Thanks again for your advice, I have no one around to advise me on mutt and here I always find answers! Thank you!

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Re: Do gearboxes break?

Post by rupert's » October 15th, 2020, 6:01 pm

svramselaar wrote:
October 15th, 2020, 7:30 am
hi
you want to buy a gearbox
do you have aproblem with yours ?
you can repair it yourself with a bit help from the g838
i can send you a pm with a drawing for the tools you need to make them yourself
and a sort of manual how to do it

george
hi svramselaar my gearbox is broken, I don't think it has repair, but anyway if there is a repair manual maybe one day I will be forced to make use of it.
I upload some images so you can see how my box is.
Greetings and thank you!
Attachments
IMG_3297.JPG
IMG_3294.JPG
caja 1.jpg
caja 2.jpg

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m3a1
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Re: Do gearboxes break?

Post by m3a1 » October 15th, 2020, 10:05 pm

I'm betting that was in a very serious wreck and somebody just put it back to work without looking at it too closely.

rickf
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Re: Do gearboxes break?

Post by rickf » October 16th, 2020, 9:12 am

Looks to me like something was dropped into it and when caught in the gears something had to give and it was the transmission case. I said they were very strong, I did not say it was impossible to break one. BUT, I will usually take severe abuse or severe neglect to do so. As long as the oil is kept at the right level and the bearings are good to start with if you buy a used one then it will give you very long and dependable service. I have seen people actually put these into service as rusty as the one in your pic and they are noisy at first but they wear in and last a very long time. As long as the bearings were not rusty. The biggest issue with these transmissions is the output seals leaking. The rear output seal is easy to replace since the small housing comes off and it can be done on the bench. The front output seal is best done when the transmission is out because it is hard to get to when installed, it can be done installed but you will use all the four letter words you ever learned. :roll: :lol: The parking brake drum seal does not leak very often and is not hard to replace and the last seal is the transfer shift rod seal and this is a royal pain and should only be done pout of vehicle. Once they are all done you should not have any issues for a long time.

What you have there with the broken case is a rarity and was not a normal failure. There was a lot more to that story.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

rupert's
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Re: Do gearboxes break?

Post by rupert's » October 16th, 2020, 1:13 pm

Okay okay, it has already been clear to me that the gearboxes are durable, (my information was not true)
I am going to buy a kit of seals for the Gearbox and if any seal leaks oil, I will change it! Thanks for your advice! I need you to decide!

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m3a1
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Re: Do gearboxes break?

Post by m3a1 » October 16th, 2020, 5:06 pm

Stick with us and we won't lead you too far astray! :lol:

halftracknut
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Re: Do gearboxes break?

Post by halftracknut » October 16th, 2020, 8:16 pm

I am glad he posted pictures of all those needle bearings...most people blame the rear end for all the noise ...most of my experience has been with those needles....they make lots of noise...and sound like a rear end....believe it or not.... Blake used to sell the kit to fix them...htn
slowest mutt east of the missippi..

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Re: Do gearboxes break?

Post by Horst » October 18th, 2020, 7:54 am

halftracknut wrote:
October 16th, 2020, 8:16 pm
I am glad he posted pictures of all those needle bearings...most people blame the rear end for all the noise ...most of my experience has been with those needles....they make lots of noise...and sound like a rear end....believe it or not.... Blake used to sell the kit to fix them...htn
I cannot agree more to HTN. See my older post on this topic http://g838.org/viewtopic.php?f=3&t=9242

BTW, I have a least one good transmission/transfer case (they are paired, you just can't change one of them). But getting it to Spain will be probably out of question.
Horst

1972 USMC M151A2 w/ROPS (ex Barstow) and M416
1962 M201 and trailer
1966 Pontiac GTO
1987 Suzuki Samurai
1987 911
1982 Ford E350 Cutaway Skoolie
Gone: 2xM35A2c, Unimog 404S, Hanomag AL28, DKW Munga

rupert's
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Re: Do gearboxes break?

Post by rupert's » October 18th, 2020, 12:54 pm

Interesting! you can see the steps to follow in case you have to change them. Great forum !! you have here a lot of information and quick answers
Regarding the gearbox ... I'm going to buy an engine that comes with a gearbox, so I already have a replacement for my mutt. :D :D :D

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