Thanks Kevin, I see the 10-3/4 clutch kit is out of stock, also I don't believe NAPA ships over the border, but I will inquire. For the trans bearings, They do show different models from front and back main shaft, so looks like they recommend a 6308NRJ. I will have to look up the difference between this and the 6209 I was originally told.
So, my apologies to anyone following this thread looking for bearing confirmation. The NAPA site only states a 'manual-4 speed', but doesn't actually state SM420 for the 6308 bearing, plus the recommendations is for the countershaft. I'm going to stick with the 6209-NR for the front main shaft and will post the comparison when I have them both in hand.
Bearing is ordered and on it's way. Figured I'd ask one more time about stealing the nice non-brass synchro out of the later model trans? Or keep the original with wear?
1953 Chevrolet 3100 261 cu inch, sm420, 3.55 rear, torque tube still,omaha orange, still 6 volt, RPO green glass, side carrier spare, all done In the DITY Gallery Video of the 261 running
1964 GMC 1000 305 Big Block V6, sm420, the next cab off restoration
As long as the dimensions are correct, either one should work OK. A SM420 is about as bulletproof a transmission as you're likely to find. The rock crawlers love them! Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
That "key" is not missing- - - -it's broken, which probably is also the reason for the damaged corners of the slots in the brass ring. The annular rings that actually grip the taper on the gear and match the speed during a shift are about halfway worn out- - - -they should come to a sharper point. That ring you found in the case is actually a spring that fits into a groove in those keys and pushes them out into the sliding shift collar. Bottom line- - - -you need a complete synchronizer assembly, or at least new keys, a spring, and a new blocker ring. Those parts might be a bit hard to find unless you can scavenge up a good used synchronizer. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
I'd suggest swapping the entire synchronizer assembly, including the sliding collar that the shift linkage engages. That rust will polish off with a little bit of work with a wire wheel on a bench grinder. Mixing and matching synchronizer parts, except for the brass blocker rings, is seldom successful. I always put a small scratch mark on the mating pieces of the slider assembly with a diamond-tipped scribe so the wear pattern of the male and female splines isn't disturbed. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
I think some of the later model front bearing retainers (the part the throwout bearing slides on) have a lip seal included. The input shaft would need to have a smooth surface for the seal to ride on. I believe the earlier ones had an oil slinger up front instead of a seal. As long as everything bolts up and the shift linkage works OK, mixing and matching parts from different years will probably be OK. Just be sure all the parts move through their full range of motion without any interference. The synchronizer sleeve with the tapered collar and the squared-off one on the later assembly should interchange, as long as there's no mechanical interference with anything. Good luck! Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Those teeth don't look bad at all. most of them have the right angle, and there's very little chipping on the ones I can see. Also look at the internal splines on the sliding collar that meshes with them- - - -the leading edges of those teeth should look similar, with a minumum of wear. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Last year I changed the 4.53s in back to 4.11s. The donor trans came out of a TF truck, pretty sure a 1/2 ton. Any chance swapping out the speedo gear would give me a little more speedometer accuracy?
Way back in the dark ages, there were speed change gearboxes that were used to correct speedometer errors. They were attached to the transmission and spun the speedo cable at a different speed, higher or lower. Internal gearing in the small rectangular box could be swapped to get the right speed correction. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
I noticed someone mentioned earlier in this thread that big trucks had the e-brake on the driveline. My two ton definitely has the original transmission (because it still has the red paint on it to match the cab. it was in fire service to begin with) and it has the e-brake on the rear wheels. Any one have a definite idea on why some were on the rear wheels and some were on the driveline. I have a spare tranny that does have the driveline e-brake.
A day without laughter is a day wasted- Charlie Chaplin When wrestling a grizzly bear, you have to keep at it until the bear gets tired, not when you get tired. 1948 Chevy 2-Ton
My two ton definitely has the original transmission (because it still has the red paint on it to match the cab. it was in fire service to begin with) and it has the e-brake on the rear wheels. Any one have a definite idea on why some were on the rear wheels and some were on the driveline. I have a spare tranny that does have the driveline e-brake.
You fire truck had it's factory trans mounted parking brake relocated to the rear because you have/had a mid mounted pump with a transfer case that disengages the rear axle when pumping, this allows the pump to turn and keeps the truck from rolling away...the parts for the parking brake may or may not be GM parts, the fire service body builder may have used parts from another manufacturer.
Mike B
Last edited by Mike B; 01/24/20227:40 PM. Reason: spelling
Any concern about the spring retainers under the clutch keys moving around and letting the key drop? The retainers are just barely long enough to hold all three in place. What are the chances that a sift in the ring caused me to lose the original key? Anyway to test their still in place after it's installed?
I have a tranny that I could not get apart if you want I could snap a few pictures .in your picture I can’t see the ring you are referring to .The picture you took is the gear cluster that I have out of the transmission case.
There two snap rings, one on either side of the hub. You can only see the 'inner' one through the clutch key holes. It's the same size as the outer one and it just barely touches all three keys. I'm just concerned that it might slip off of one and cause the key to fall out. It would only be about 3/8" movement to expose one key...
That's the seal for the rear of the ball where it slides over the torque tube.
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
Ya, to use later synchro, you need whole front shaft. Front shaft not compatible with earlier models without seals. Either I drill/tap new holes, or keep looking for synchro's.
The one with the seal is the way to go as it won’t leak oil if you are parked on a hill like the Novak site explained .Can you use the newer case that matches the front cover .All the gears I would think fit .worth a try although more cleaning
Ya, that's the only advantahe that I can see for the later model. My first choice is to replace the synchro and button it up. Will see what I can find...
Goach2 If it was mine would find a drum brake for the open driveshaft system and use it,that way you'll have a great lever brake and modern u-joint system. when you find the drum brake a bolt in drive shaft may be there with it. Also the lever brake will hold a pretty good load because it's working thru the differential gear ratio's. only down side is may need to re-line the drum brake,have been studying that 'cause mine needs it !!
