M38A1 steering box

[chuck]

Morning all.
After lurking for a while,and learning so much from all of you, I decided to join the forum.
I have a 1952 M38 that I have been restoring for many years. Just recently I began the rebuild of the steering box and quickly found out it is M38A1. Is this a better box? Is the steering ratio different?

[rdsar2k]

From what I've read the output shaft (the one with the two pins) is a larger diameter. I have also read the steering ratio is better. The gear box with the larger diameter shaft was used on the CJ6 and the V6 model CJ's. I've gleaned this from the internet researching parts for my M170 (M38A1's larger brother) gear box not from experience.

Hope this helps. Others I'm sure will add.

[chuck]

Thanks

[wesk]

I believe the important thing is to not install a faster steering ratio gear box in the jeep that came with the slower ratio box.

M38 - Ratio 15.4-13.5-15.4

M38A1 - Ratio 19.1-17.1-19.1

[chuck]

Sounds like the M38a1 is the best combination in my M38 since I have a Warn overdrive.
I need a detailed pic of the horn inner rod set up,since I have no parts at all to go by except for the small horn button and nut.

[rdsar2k]

In downloads section the parts manuals are available for free and show breakdowns on assemblies and repair manuals describe repairs. I had the same issue and used the parts manual to give me a visual aide

[chuck]

Sorry to add to the confusion about steering boxes. I think I have it straight now.Wes said not to use an M38A1 box in a M38 because it will be squirely at higher speeds. How squirely?? My M38 has overdrive so I could be driving up to 50mph at times. I have a pretty good M38A1 box and a NOS sector shaft to put in it for trade towards a NOS or recently rebuilt or known good M38 box in the NH area. Any help would be greatly appreciated.
1952 M38 #69309
Born 6-52

[wesk]

I think what I said was look at the ratios and avoid placing a fast ratio in a slow ratio jeep. That said I need my coffee before I decipher which ratio is the faster ratio. If I stare at center point ratios long enough I think I recall that the M38's 13:1 is 13 wheel turns to one full sweep of the front wheels and the M38A1's 17:1 is 17 wheel turns to one full sweep of the front wheels in theory since we know the ration changes as we get towards each side. That would make the M38 the slower and the A1 the faster. That should mean don't put the M38 in an A1 but the A1 in an M38 is ok.

Does anyone read this differently?

[rdsar2k]

I liken it to a differential. The higher the number the more turns it takes to move the wheels (the slower the vehicle). I agree the m38a1 seems like the safer gear box.

[chuck]

Now I'm really confused!Look at the post that I found datedJan 31 2006. I don't mean to be a PITA but I don't want to get killed driving this thing either. I do appreciate everbodys help.
Thanks again!

[wesk]

Not sure what that post says but if I said the opposite of what I put above I was wrong then. Like I said today I need my coffee before I decipher the ratios. That is why I posted the ratios so one could do his own math.

[Stir-stick]

I'm Lost . Does the m38 and the m38a1 share these common components? Pitman Arm , Draglink ,Tie Rod configuration,Steering Knuckles,Wheels,Tire Sizes??? Why would one not work on the other Could it be a weight problem??? HELP!!! STICK

[wesk]

Both the M38 and M38A1 ORD 9's are on our download page for free.

Just download them if you don't have them and print the pages for the steering parts. Then lay the pages side by side and compare part numbers.

Some parts match and some don't. The steering boxes are two different boxes. The M38A1 came out with the heavier tie rods.

Most parts can be interchanged between the jeeps but the important part the gear box has safety issues if you swap the faster ratio box into the slower ratio jeep. Will it fit? Yes. Will it behave well above 40 MPH? No.

[chuck]

Has anyone actually driven a M38 with a M38A1 steering box above 40MPH? What is your opinion? Someone on this forum must have, since good M38 boxes are getting hard to come by.

[wesk]

Why would one not work on the other Confused Could it be a weight problem??? HELP!!! STICK

The M38A1 was built with 12 more horsepower and was capable of going a little faster than the M38. Thus the factory's wisdom was to make the straight ahead steering less sensitive. Also the spring rates are not the same and the front springs on the A1 went to reverse shackles.