in my 55 f100 when my overdrive is pushed in and I downshift from 3rd to 2nd the second gear freewheels can anybody tell me what the likley cause is? im reading my service manual now but it is confusing

 

I'm trying to put together an overdrive for my 55, and interested in the response you get. Maybe another post will push your question to the top of the threads, and generate a response. Keep Askin, David

 

I had a 1952 Mercury car with a similar overdrive lever. With the overdrive button in one can engage overdrive in 2nd gear at a certain speed by letting off the accelerator. Below that speed the transmission would freewheel if let up. Could even do the same in 1st gear. Your truck may behave normally in the same way.

Fred K.

 

I drove the truck for a couple of hours yesterday and with the overdrive pushed in when you gear down to second it does freewheel. eventually at a low enough speed I would say around 25-30 if you rev it up a bit the gear will catch again. From reading the manual it seems to be right. So it seems if you are driving around town the lever should be out for direct drive with the overdrive engaged for highway use. After the couple of hours it all seemed to work better probably a little stuc after sitting for 10-15 years!

 

There is a speed controller on the OD that determines when the OD gets engaged. I guess that it kicks in around 30 mph. I know in my '59 you can't get it to engage OD in 1st gear. 2nd gear you get to the point when it's time to shift, let off the pedal, and the OD would shift in.

 

Taylor55, the o d trany is designed to freewheel, it has a set of rollers that lock in under load, when you let off they retract and you get the freewheel. There were some questions about speed, the govenor completes the circuit at about 28-30 mph this allows the solenoid to lock the trany into o d at highway speeds and drop back into std at low speed.

Deuced, the first thing you want to look for is an o d unit that has a casting number of "R10F", this is the o d used on '53 and later tranys. The "R10E" is an earlier version. Some of the internal parts are the same. But NOT the PAWL. Be careful here, I have seen people put the R10E pawl in a R10F box, it works for awhile, then rounds on the edge and no more locking into o d. The o d tail unit on a truck is the same as a passenger car, on the truck (light duty) the input shaft has a larger pilot and the overall diameter of the shaft is larger. You should be able to put a truck shaft in the pass box. As far as using the non o d box, you would need to find an o d housing (gasket might work), bolt it to the back of the box and drill a hole for the reverse lock out shaft. When my o d relay died I bought a universal headlight relay, put a jumper between two points and have been running it for several years. As far as bolt up, I used the original 6 cyl bell housing on the back of my 292. I would start by trying to find a h d trany that you can get the bolt pattern from then compare to the pattern on the l d .

 

Thx. Rustcollector, The casting numbers are invaluable.

Eureka! I think I hit it, I bought a 53 Truck 3 Spd. Overdrive from behind a flattie, and while I was assured it used the same bellhousing as my 55 239 OHC Y-block, and was an Approp. match, this is the first specific confirmation I have found of it's interchangability.

I was sweating it, but you know: Every once in awhile, even a pig finds a truffle in a field of patties.

David

 

Taylor55, the o d trany is designed to freewheel, it has a set of rollers that lock in under load, when you let off they retract and you get the freewheel. There were some questions about speed, the govenor completes the circuit at about 28-30 mph this allows the solenoid to lock the trany into o d at highway speeds and drop back into std at low speed.

Deuced, the first thing you want to look for is an o d unit that has a casting number of "R10F", this is the o d used on '53 and later tranys. The "R10E" is an earlier version. Some of the internal parts are the same. But NOT the PAWL. Be careful here, I have seen people put the R10E pawl in a R10F box, it works for awhile, then rounds on the edge and no more locking into o d. The o d tail unit on a truck is the same as a passenger car, on the truck (light duty) the input shaft has a larger pilot and the overall diameter of the shaft is larger. You should be able to put a truck shaft in the pass box. As far as using the non o d box, you would need to find an o d housing (gasket might work), bolt it to the back of the box and drill a hole for the reverse lock out shaft. When my o d relay died I bought a universal headlight relay, put a jumper between two points and have been running it for several years. As far as bolt up, I used the original 6 cyl bell housing on the back of my 292. I would start by trying to find a h d trany that you can get the bolt pattern from then compare to the pattern on the l d .

 

Taylor55, the o d trany is designed to freewheel, it has a set of rollers that lock in under load, when you let off they retract and you get the freewheel. There were some questions about speed, the govenor completes the circuit at about 28-30 mph this allows the solenoid to lock the trany into o d at highway speeds and drop back into std at low speed.

Deuced, the first thing you want to look for is an o d unit that has a casting number of "R10F", this is the o d used on '53 and later tranys. The "R10E" is an earlier version. Some of the internal parts are the same. But NOT the PAWL. Be careful here, I have seen people put the R10E pawl in a R10F box, it works for awhile, then rounds on the edge and no more locking into o d. The o d tail unit on a truck is the same as a passenger car, on the truck (light duty) the input shaft has a larger pilot and the overall diameter of the shaft is larger. You should be able to put a truck shaft in the pass box. As far as using the non o d box, you would need to find an o d housing (gasket might work), bolt it to the back of the box and drill a hole for the reverse lock out shaft. When my o d relay died I bought a universal headlight relay, put a jumper between two points and have been running it for several years. As far as bolt up, I used the original 6 cyl bell housing on the back of my 292. I would start by trying to find a h d trany that you can get the bolt pattern from then compare to the pattern on the l d .