3-speed questions

[billinkw]

Hi, i recently bought a 71 bronco that I have been working on building up. Thanks for all the electrical help so far everyone!

I have never driven a 3-speed before but it seems to be shifting at very low speeds. When i shift into third gear, its around 20-30 (I don't think the speedo is calibrated) and the engine is at high rpm. By the time i hit around 40, the engine is screaming. Any ideas or is this normal. Thanks.

 

[Broncobowsher]

Is the transfer case in low range? If the shifter is fairly close to the dash and won't go forward then it is in low range. A '71 should have the T-shift transfer case. The shift pattern is a straight line forward and back.

All the way forward is 4WD low range
Back one notch (not a factory listed position) is 2WD low range
Back one more is nuetral
Back one more is 2WD high range (normal operating range)
All the way back is 4WD high range.

The transfer case can be a bit of a fight to get to shift, No need to force. It doesn't shift well if gears are not lined up (internally) or if the gears are bound up. Just moderate pressure is all that is needed, maybe a little driving input as well.

But do start by making sure that you are really in high range. If it still does in and you are sure you are in high range follow the "gear ratio check" in the tech section. Lets see what the gear ratio is. Use the instructions on this site, not any "jack a wheel up and spin it" tricks, they are prone to errors.

 

[billinkw]

Thanks Broncobowsher, i was gonna do the gear ratio check this weekend. Ill double check the transfer case gear tomorrow. It is hard to shift a bit, it has a floor shift conversion and its really close to the 4wd shifter and it seems like it was hit a few times while shifting into 2nd.

 

[daren]

That is about how it is for me with my 3 speed. When I got the truck from my father in law he told me put in some earphones and shift when it seems/feels about time. I always thought it seemed like it was screaming also and about to explode or something. But then I found this which gave the approximate shift speeds. http://www.broncohio.com/tech/73broncomanual/73man-16.JPG
Hope that helps

 

[bknbronco]

When i bought my 68 it had tiny tires on it and you would have to shift into 2nd before you got accross a intersection....that or just start in 2nd. I have 4.10 gears. You might have the same gearing.

Now that i have 33's on i dont have to hit 3rd until maybe 45 or 50. much better with bigger tires.

Youd def know if its in LO!

Also something to think of.....when i had on my stock fan the motor made so much noise you def knew when it was time to shift because it was like a airplane getting ready to launch off a ship! I changed to a clutch fan and its now really quiet. You feel the motor instead of hearing it. The stock fan is way to loud and makes you think you need to shift earlyer i think.

 

[jdominguez]

I've got 33s on mine and would say the shift to 3rd is generally around 40-50mph depending on how aggressive the driving is at that time. First is good up to about 15mph and second runs out pretty quick thereafter. Once I hit 3rd though the Rpm's are very low. It's definitely a cruising gear for my rig.

 

[billinkw]

Now the transmission is winding pretty loudly. I double checked the transfer case and its in the proper gear and the shifter is stuck. I guess its time for a rebuild. Anyone know any good mechanics in the Austin area?