Deuce RPM Questions

[panzerjunky]

Hello Gents
Long time no talk
My M35a2 turbo runs 60 mph @ 2600 rpm Folks tell me this is impossible and it should be pegging way higher on the RPM scale tires are stock gauges are stock the only thing diff is I turned up my idle a tad as she was surging a bit after I fixed my IP it is idleing at about 900 RPM i am going yo bring it down to 750 800 as I think the surge is gone ( must have ben Air?)
Anyway Does my RPM to speed ratio seem correct or is there something a little off?
Thanks Jerry

 

[WillWagner]

Tach could be off, check it with a phototach or, there is a brazillian made trans that has a different ratio that I have heard will be a 60 MPH transmission.

 

[markmontana]

Did you verify your speed with GPS?

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[wsucougarx]

I hope this doesn't turn into a connecting rod issue thread

 

[clinto]

One of the gauges is wrong.

 

[mcmullag]

crawling thru mud

Let us know how that turns out.
Best of luck.
These trucks, with their double reduction axles
were really not made for that kinda high speed.

Go speed racer, go speed racer, go........

 

[wreckerman893]

Are you running stock 900x20 tires?
This may be relevant or not.....my M275 tractor shows 65 at 2800.
I suspect (but have no proof) that there are/were higher geared transmissions or diffs that made their way into some trucks.
Or my speedo could be FUBAR.

 

[gringeltaube]

..................
Anyway Does my RPM to speed ratio seem correct or is there something a little off?
Thanks Jerry

57-58mph would be correct, 60 is just a bit optimistic.

G.

 

[panzerjunky]

Ok Thanks for the info
As for being optimistic it burrys the needle and the tac is only 2700 pushing 2800 I don't run it over that. I had my wife pace me in her car and the speedo is right on the tires are 900X20.
What is the deal with this Brazilian Trans or were you pullin my leg. The reason I ask is the guy I bought it from said " you will be very happy with the top end and the fuel economy" but never eluded to why

 

[Goose2448]

I am no deuce expert, so One of you deuce experts correct me if I am wrong.


The RPM gov is set to 2650. So my guess is that the tach is off or the governor has been reset. And If I do remember right over the preset RPM is just waiting for a problem.

Just my

 

[MDSA]

As Clinto says, one of the gauges is wrong.

When I bought my Deuce from a private individual, he claimed it would do 65. I didn't want to argue but knew that was wrong. Sure enough, it shows the mph needle well past the 60 at around 2400 rpm's. My son was following me and said I was only doing 52-53. The speedometer is off by about 10 mph.

 

[cranetruck]

Referring back to the old PS mags, here is what they say about max rpm for the multifuels when they were new to the service in 1967:

 

[CGarbee]

Keep in mind also that there is more than one speedo adapter (between the transfer case and the speedometer head) in use. Needed do to the use of different diameter tires by the military in OEM applications with the rest of the driveline and guage parts being the same in order to get correct speed readings. If somebody has changed out the adapter and gotten the wrong one in, your speedo will be off.

I don't have the adapter part numbers handy at the moment...but you should be able to find them in the TM's (one for use in a M34 series truck with 900x16 tires, one for use with 1100x16 tires).

 

[Tanner]

I hope this doesn't turn into a connecting rod issue thread

Everyone knows that the connecting rods have NOTHING to do with the increased speed - some of the trucks have longer pushrods and slicker oil in their engines...

'Tanner'