I’ve got this transmission in my service truck. As of late if I’m just cruising along in 6th gear (which is towards the dash) it will slide just a bit towards neutral and out of gear. Doesn’t do it if I’m on the throttle and under load. Only when I’m easing along like through town. I know this transmission doesn’t have springs and detent balls like a big boy transmission but I really don’t know much about it. Just want to catch it and fix it before it becomes a real problem. Anybody have experience with this?
Yes that's a tunnel type transmission-get a manual that's a must and prepare to open your wallet.
I found the parts manual online.what’s worn out?
That I can't say because I'm in the same boat I would figure on a disassembly to find the problems because there probably is more than one issue- usually is. How many miles on it?
No idea the miles. Truck has 330k. Bought it at 306k but transmission has a reman tag and the flywheel housing was new so I don’t know the history of the truck. Still shifts fine and doesn’t grind or growl, just slides out. Also recently I switched from 80w90 to 50 weight Castrol syngear oil. Any chance that has anything to do with it?
I think I already made a reply about that in a previous thread.
Guess I never read that thread
HeavyEquipmentForums
The transmission does have detent balls and springs. Did you find the manual if so can you send me the link or the model of the transmission. There are grooves in the splined collars that the sliding clutches slide on. those grooves help hold the the collar in gear. These grooves may be wearing away. Before you do anything inspect the U-joints for wear especially the one at the rear of the transmission.
U joints are tight. Transmission model is a ES066-7B
I seem to recall an update to those sliding fog clutches. Early versions were straight cut gears relying on balls and springs to maintain engagement. Update was back cut gears and sliders. The harder you powered in, the harder they gripped. Its been a long while, but worth looking into. Also, yer springs could be getting weak.
There are detent springs under the shifter tower. Remove the tower and gasket and there is a stamped steel plate under the tower with 2 drive in rivets holding it in place. Under the plate is 4 springs and detent balls. It would be a pain to do through the hole in the floor but probably doable. It might solve your problem. The spring is G7 in the parts breakdown and there are 4 of them 3 at the back of the tower and 1 in front. you will also need gaskets M-4a and M-4 and 2 of rivet m-3. Pull the tower out and put a couple bolts in to hold the plate M-1 from going flying when you pry under the plate. Leave about 1/4" of thread above the plate so it can pop up from spring pressure. Also put a rag or something over the hole in the plate so the rivet don't fall into the transmission.
Thank you. I’ve had the tower off but never had the m1 plate off
If that does not fix the transmission jumping out of gear then 6th gear and synchronizer and hub will need to be replaced. The sliding clutch teeth are tapered to hold them in gear and over time the taper wears and no longer holds plus the hub has grooves that hold as well and also wear.
What's the price like on hard parts? the fact it's spicer it can't be cheap. The RMX 10spd parts are ridiculous. I quit rebuilding those a ways back. In a reman that 7spd averages $3,400.
I have rebuilt a few of the 7 speeds. Parts are more here in Canada. I don't know about the quality of the rebuilds but around $4500 here in Canada. I could rebuild one for about the same price.
That's pretty spendy for a seven spd.
$4500 Canadian is about $3200 US.
What I have found U.S. is $3,400, that's still a chunk of money for a 7 spd.
I had one go sour in an international . it got to the point where it would come out of 6th on a pull hard enough to slam back and try to go into 7th. I replaced it with a 6 spd. fuller it to was a previous reman.
I had a 6 speed fuller in a service truck years ago. It was fine but I do like the donkey low in my 7 for hard chance spots
If you had a 7 speed that was falling out of 7th, is that something that will migrate to the other gears too? Looking at a truck, and with our use not sure we'd ever really use top gear, but if it's a warning of hell to come rather not touch it.