View Full Version : 76 FJ40 4 speed issues

07-10-2008, 12:12 PM
Thought I'd start a new thread so that I don't clog up the BOWTGW thread. So here's a brief history. When I got the truck in March, I noticed that occasionally if I shifted out of gear into neutral when stopped, that I could not get it to shift back into gear. In those cases, I would typically roll it a few feet forward or backward, and it would engage properly. Once in gear, I never had/have any issues shifting between gears. The only other thing I've seen is that it will pop out of 4th gear when decelerating.

Fast-forward to yesterday. Everything was fine for the first 1/4 of the trail. After the steep decent following the cattle guard (and that whacky Jeep juy), I got to a spot where I was wedged between a couple of rocks. I threw it in reverse to change my line, but when I shifted it back into neutral, I couldn't reengage 1st gear, and worse yet the transmission was still in reverse.

I shifted the trans case into neutral, and got a strap to the meadow. At that point, I was able to shift it out of reverse, and into first. Then put it in neutral, and couldn't get it to re-engage. Messed around a bit again, and got it back into first. At that point, I left it in gear, and was able to drive it out and get it home. As long as I'm engaged in 1st - 4th, I can upshift and downshift with normal behaviors. But if I go out of gear, then I can't can't back in with out a lot of good juju.

There were a lot of weird grinding and whining noises coming from the transmission on the way home, and sometimes while driving down the road, the truck would start hesitating and jerking a bit. I let off the gas a bit, and then gas down again, it would "correct itself."

Kinda sucks, cause the 40 is my DD right now. The Tacoma is in the shop having some work done. I'm heading to Michigan tomorrow for a week, so I'll have to look at it when I get back. But if anyone has suggestions, tips, or a spare 4 speed around that I could procure (if it comes to that), please let me know.

07-10-2008, 12:17 PM
Did a bit of reading earlier this morning - AWESOME thread Jeff. Some good details on FJ40 tranny and trans case install/removal mixed in there.:thumb:


07-10-2008, 01:53 PM
If you want another 4 speed transmission to try out, let me know. I think I have 4-5 left in the garage.

07-10-2008, 03:19 PM
Yep 4 speeds are a dime a dozen, and Bomb Proof, Hit up Treeroot and get another one to slap in there.. should be cheep and not to hard.. ;)

07-10-2008, 03:28 PM
I could swear I've seen/read somewhere that it is possible for a H42 tranny to get stuck in 1st and Rev at the same time; I thought it was on the LCML but now that I think about it I think it was in a TT somewhere. I've read through about 20 recently (shooting to get a copy of all the color issues at least), so it could be in any one of them. I think it was a tech article by Mark Whatley. I'll see if I can find it tonight, I'd rather skim through TT than clean the apartment...:( :eek:

07-10-2008, 06:42 PM
Okay, here is what I found: this is the article I was thinking of, though it doesn't necessarily cover the exact issue; there may be another one somewhere but I'm pretty sure this is the one I was thinking of.

"I just replaced the clutch on my stock 1984 FJ60. I installed the shifter and it won't shift. I then took off the shift tower to inspect for problems and everything seems fine, reinstalled it and it still won't shift. Do you know what the problem is?" Dave Berry

Make sure that the tranny is in neutral before you insert the shifter. Then make sure you insert the shifter so that it is in the neutral position too. This should solve things. What has happened is that the transmission was in gear when you inserted the shifter. The shift lever wound up engaged in a shift rail other than the one which actuated the gear that it was in. The design of the tranny will not permit the rails other than the one engaged to move. This is to prevent the tranny from being engaged in two gears at the same time.

This can also happen if you are resting your hand on or holding on to the shifter while negotiating rough terrain. Wear to the shift mechanism can allow the shift lever to be pulled between the rails and result in the same problem. The rail that is engaged by the lever is different from the one that is engaging the gears.

"In a response to Dave Berry in the Sept-Oct 2001 Toyota Trails, you said: "This (wear causing the transmission to engage two gears at once) can also happen if you are resting your hand on or holding on to the shifter while negotiating rough terrain." Well, I have to hold my shifter while descending steep slopes to keep my 1986 FJ60 in gear. Am I wearing out my shifter/transmission? Can something be done to keep the thing from jumping out of gear at the least convenient moments? Or does its slipping out of gear indicate the need for repair or replacement of parts?" James Peavler

Actually what I wrote was: "This can also happen if you are resting your hand or holding on to the shifter while negotiating rough terrain. Wear to the shift mechanism can allow the shift lever to be pulled between the rails and result in the same problem." The "This," and the "same problem" mentioned here are winding up with a locked transmission that will not shift due to the lever being in an incorrect rail slot.

This really doesn't have anything to do with the problem that you are experiencing. If your transmission is popping out of gear in overrun conditions this is indicative of wear. Holding it in is better than losing control and will not cause major problems when only done for short periods. But ideally your tranny needs some attention internally.

Sounds like your transmission needs "some attention internally" :(

Now I have to go clean the apartment, that look altogether too little time - it was the first issue I looked in :doh:

07-10-2008, 06:56 PM
Thanks Matt - appreciate the research. Interesting note about "holding the shifter." I'm sure I did it on the trail, but because my tranny has a tendency to pop out of 4th, I often rest my hand on the shifter to keep it in gear on the pavement. Probably something the PO did as well.

Treeroot - Thanks for the offer, and I'll probably take you up on it when I get back into town. It would be ideal to swap in a new functional 4 spd, then I can open up the old one and see what's up.

07-11-2008, 12:07 AM
HI Matt,

After inspecting the usual culprits for your symptom on the trail yesterday, and finding nothing out of the ordinary (other than your tranny would not shift), here is what I would do if it were my rig. And I hate to be bearer of bad news, but we talked about it already so you already know.

Pull the tranny hump. Kinda PITA job but you gotta do it anyway. Undo the PITA spring loaded shifter retainer. I have now learned that a 4 speed goes clockwise to undo it, a 3 speed goes CCW. Note that up this point you don't have to pull the tranny t-case or anything else and all you are dealing with thus far is pulling the seat frames, tranny hump and next:

Undo the top cover of the tranny. From there, you can learn the deep, dark secrets of an H42 (or H41, they are the same inside) and it may be that the source of our shifting issue, non shifting issue will become clear quickly. Watch for an be prepared to catch balls in mid air propelled by springs that hold them. Do not let them become projected to dark recessess of your garage. Do not ask me how I know this other than to be prepared.

Once you have the top off the tranny, it's operational principles will be revealed and most likely, the cause of your issue on our trail run yesterday will be obvious. When I took my first tranny apart, it was an "Oh I see how that works!" moment, and would expect so for you too. Good luck and happy cruisin'!

PS, I'll help you out!

07-21-2008, 03:09 PM
Thanks Jeff - I REALLY appreciate it. I'll have my Tacoma back this week, and then I can start to plan for what to do next.

But.....the saga continues. I started it up on Sunday to let her run, and for me to play around a bit, and initial indications were that I had no trouble shifting gears in my garage. Hmmmmm.... So with my wife safely at home and available should I need a tow, I ventured out in the 40 to run a couple errands. I had no trouble at all shifting between 1st and 4th, and heard no weird metal/grinding noises coming from the tranny box. :confused: Granted, I kept it in a gear at all times (no neutral), but shifting was normal, and I was never locked out of any gear.

So at this point, it seems that I can get around town in it. But I've also lost all confidence in taking it anywhere far away or on a trail. Whatever problem is in there, it seems to be conditional, but I don't know under what condition(s). Guess I'll have to open it up...

I'm just bummed that it happened right in the middle of prime-time 40 season. :(

07-21-2008, 03:48 PM
The locked transmission problem that subzali is quoting is a common problemon split trannys. a plastic bushing under the shifter wears out and locks the trans in gear. that bushing is not used in the older fj40 trannies.