I am in the middle of a 1JZ swap and I have just finished cleaning up my R-154 from the 7MGTE. I have the front and rear main seals for the tranny that I am going to put in, but I want to make sure I complete all preventative maintenance I can to the tranny before it gets mated to the 1J. I remember (it's been some time since I drove the supra), that sometimes when attempting to put the shifter in reverse to back up, it won't go, unless I put it into first gear as well. A couple of my dad's mustangs would do this as well. What is this an indication of? Is something worn that I can easily replace without rebuilding the whole tranny? Thanks for any and all info and help!
Why must I sometimes put R154 in 1st gear to get into reverse?
- Thread starter nctexan
- Start date
supranasty;1514843 said:
WTF are you on about "round off teeth"?
OP: If you have a worn box or badly adjusted clutch the input shaft can drag a little (thick cold Oil will do this also) turning the cluster gear which will make reverse clash on engagement, pushing the shift toward a forward gear stalls the cluster allowing reverse to engage while everything is stopped, wait a few seconds and everything will spin again and the crunch returns.
Thanks IJ My answer was wrong, as per his question .You have it correct . The Reverse Gears do round off causing poor meshing though because of the input shaft drag or spin. I have redressed reverse in my gearbox with a drimmel tool to return the edge of the gear to near original form which is lost from usege in 100k mi.trannys . Just something I've learnt from rebuilding three gearboxes and TIPS I got from pros LIKE You .I should give better answers, 5am was kind of early .
Ummm if the cluster is rotating when you try to engage reverse you could have dremelled hello kitty shapes on the teeth and it's still going to clash 
Not many people here would have heard of non syncro crash boxes let alone driven them, you have no idea just how good modern boxes are
Not many people here would have heard of non syncro crash boxes let alone driven them, you have no idea just how good modern boxes are
Agreed , The tip I was told only helps it. Sticking your finger in a "fan" is hard too . LOL
nctexan , I would upgrade with marlin crawler if its an old high milege box. If you plan to make some high power mods to the 1JZ for sure.
nctexan , I would upgrade with marlin crawler if its an old high milege box. If you plan to make some high power mods to the 1JZ for sure.
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IJ.;1515205 said:Not many people here would have heard of non syncro crash boxes let alone driven them, you have no idea just how good modern boxes are
Ha !
Brings back memories of learning to drive in my father's 53 chevy truck.......
Had to double clutch that old dog even on up-shifts.
4U2QUIK
1UZFE SWAP DUDE!!!
IJ.;1515205 said:Ummm if the cluster is rotating when you try to engage reverse you could have dremelled hello kitty shapes on the teeth and it's still going to clash
Not many people here would have heard of non syncro crash boxes let alone driven them, you have no idea just how good modern boxes are
synchros are a gift from god....... I had a 1937GMC truck that I drove from where I purchased it to my home 4 miles away. I quickly learned what double clutching and rev matching was all about.
So from what I've read, it's a pretty common condition, that does not necessarily need to be fixed to ensure proper operation of the tranny.
I'm not going for any big HP numbers, no more than 350. The tranny has about 155k on it, I'm the second owner and I've never abused it, the first guy was an older man in FL.
I'm not going for any big HP numbers, no more than 350. The tranny has about 155k on it, I'm the second owner and I've never abused it, the first guy was an older man in FL.
IJ, my R154 did this until I replaced the shift bushings, as that my stock 'green' ones were apparently shredded. With the marlin crawler bushings I never have to go to 1st to get to reverse anymore, it just pops right in. Could this be the problem?
IJ.;1515205 said:Ummm if the cluster is rotating when you try to engage reverse you could have dremelled hello kitty shapes on the teeth and it's still going to clash
Not many people here would have heard of non syncro crash boxes let alone driven them, you have no idea just how good modern boxes are
I can't say I've ever driven non syncroed transmission car but unfortunately a new breed of ignorance is resultant of modern transmissions. I love listening to people tell me they dont need to rev match or double clutch when driving hard because they have syncros in their trans. Then they complain that the syncros were defective when they go bad. Notoriously 3rd gear on hondas.
Double clutching on a tranny with syncros = retarded.
Rev matching is for smoother shifting and car control (heal toe in corners).
Rev matching is for smoother shifting and car control (heal toe in corners).
Poodles;1516689 said:
Only when your banging gears, in case your rev match is a little off. You just delay your clutch disengage a tad. You realize how a effective it is when you drive a car with a trans that already has fried syncros.
That's the only reason to learn to do it is if the tranny is fucked and you have to limp home.
A properly working syncro requires zero rev matching.
A properly working syncro requires zero rev matching.
Poodles;1516924 said:
And like anything else, the more you use them the faster they wear out, no?
Poodles;1517303 said:
No but I do minimize their use when driving casually. Thats primarily for fuel economy though. If I burn up my brakes, I can change them...doneski. I trash a syncro, I have to live with a gremlin or remove the trans and take it apart, which means downtime, workspace, tools, money, and experience that I dont have. I could pay to have it done but again, downtime, and money I dont have.