OlBlue Posted March 21, 2012 Share Posted March 21, 2012 I usually like to wait until I have researched and hit a brick wall before putting out a post...but thought I would make an exception today. Driving home today in some very snowy conditions, after passing a few lesser vehicles hung up and stuck along the way I managed to get my self stuck in a drift. Having negotiated my way out of this same predicament on more than a few occassions, I tried moving from forward to reverse a few time with one front wheel spinning and one back wheel spinning etc. I hopped out and did some shovelling under the front diff/rear diff and began trying to drive out again. At this point I noticed...no wheels were spinning, and the transmission was not engaging at all. Not in D/R/1/2...nothing...I am convinced this is not good. This is a 95 SE, with an AT, fluid levels looked and smelled fine a week ago (routine check), no recent sign of any leaking AT fluid in the snow, no issues with the trans with exception of reverse not always being there. I took a quick peak underneath after getting towed home (first time for everything), and the drive shaft didn't seem to have any play in it and nothing unusual at first glance. Since the storm is still going I thought I would throw this out for opinion on where to start looking when I can get it inside. Any takers? Link to comment Share on other sites More sharing options...
1994SEV6 Posted March 21, 2012 Share Posted March 21, 2012 This sounds pretty typical of the safety mode for the transmission. Sometimes the transmission will lock itself into "limp home mode" if there is excessive wheelspin. This has been mentioned on the forums a lot recently with "broken transmission" thread or something like that. To get it out of fail-safe mode you have to do something like turn it on and off and then turn it on without starting it then wait 8 seconds and look for the flashing transmission mode light. Let me see if I can find it for you Link to comment Share on other sites More sharing options...
Slartibartfast Posted March 21, 2012 Share Posted March 21, 2012 (edited) ^+1, the trans gets confused and locks into third, which isn't much use when you're stuck in a snowdrift. Shut it down, start it back up, and see if it goes then. If the E-AT light's flashing, the trans computer thinks something's wrong; normally it'll illuminate at startup, then go off. (I think it stays on if you've got it in 'power mode.') Failure with these is usually more gradual. Unless your torque converter gave up, my money's on the computer being confused. Edited March 21, 2012 by Slartibartfast Link to comment Share on other sites More sharing options...
OlBlue Posted March 21, 2012 Author Share Posted March 21, 2012 Well, I went out and gave it a try hoping a good cool down would help. The dash lights were not much help since the belts were slipping due to the snow that had blown under the hood. Still no dice with the trans engaging. I have been searching some of the old threads, on the safe mode. Once I get it dug out and pushed in I will give it a going over. Good times. thanks Link to comment Share on other sites More sharing options...
Trogdor636 Posted March 21, 2012 Share Posted March 21, 2012 The fact that reverse "hasnt always been there" makes me think your auto-tragic might be worse off than being in safe mode. I've always thought reverse was the first to go. Good luck digging it out and I'll cross my fingers for ya. Link to comment Share on other sites More sharing options...
Precise1 Posted March 21, 2012 Share Posted March 21, 2012 ^ That! Download the FSM from the Garage section, it has a decent diagnostic section, but honestly, that doesn't sound good. B Link to comment Share on other sites More sharing options...
OlBlue Posted March 21, 2012 Author Share Posted March 21, 2012 Thanks fellas, I am pretty sure this is more than a electronic glitch. I was going through the FSM after my initial post and haven't found anything that resembles a simple problem/fix. Has anyone heard of a complete failure like this? Can't wait to get a look at it. It was -28C with winds over 90 when she stopped working, so I was pretty I hadn't over heated in the 10-15 seconds I was trying to maneuver out. Maybe I should have taken the "if you need a plow...move" advice earlier? . Link to comment Share on other sites More sharing options...
Slartibartfast Posted March 21, 2012 Share Posted March 21, 2012 (edited) I missed the bit about reverse. Yeah, reverse is the first thing to go on these... the cooler clogs, the clutches don't fully engage, they slip, and they wear out. IIRC, the material wearing off the clutch worsens the clog. Maybe try bypassing the transmission cooler (not like you need one in -28C, right?). If the cooler's clogged, but the clutches aren't fully hosed, this might get it going again. Past that... I dunno, are there junkyards on Hoth? Xterras and later Pathfinders have more durable automatics that'll bolt right into a WD21. Edited March 21, 2012 by Slartibartfast Link to comment Share on other sites More sharing options...
OlBlue Posted March 22, 2012 Author Share Posted March 22, 2012 That cracked me up. Unfortunately the owner and operator of Hoth-Nissan ordered in the back up trans before the bolt on Xterra thread started. Link to comment Share on other sites More sharing options...
silverton Posted March 22, 2012 Share Posted March 22, 2012 I'm not sure why people are still stuck on the cooler clogging. That's not the problem. The problem is poor transmission design, but they still last longer than Nissan ever intended them to. Japanese vehicles aren't even meant to go past their first timing belt change on their island! But these transmissions go 170-200,000 miles before the trans let's go, even with routine maintenence. Link to comment Share on other sites More sharing options...
OlBlue Posted March 23, 2012 Author Share Posted March 23, 2012 (edited) Not sure what the problem is, or what caused it (yet) but will be sure to let you guys know. I hope to get the vehicle pushed into the garage this weekend for a once over. After looking over my spare AT and thinking about the engine swap on my 91 last summer, I am thinking it would be much easier to pull the engine with the trans still connected, install the replacement (and some leaking oil seals) on the hoist/floor than just dropping the trans and trying to install then replacement from underneath. I don't like the idea of wrestling with that front diff again, which goes with removing the engine but what I have read on the TC, and what I remember about lining up the trans to the engine I think it might be the way to go. If I pull the works, disconnent the deceased trans and place the engine in a cradle, line up the new trans using the hoist, and drop the work back in I wonder if that would be simpler exercise? I realize either way it is a big job, and from what I have seen posted both have their challenges. Will let you know how the diagnosis goes. Good times. Edited March 23, 2012 by OlBlue Link to comment Share on other sites More sharing options...
silverton Posted March 23, 2012 Share Posted March 23, 2012 If you have a transmission jack, it isn't that hard. you push the torque converter on to the splines of the transmission before putting it up, then line up the holes on the flex plate. it's fairly simple! Basically, just keep rotating the torque converter and pushing in on it, there should be about three steps it goes down on to. Link to comment Share on other sites More sharing options...
Precise1 Posted March 23, 2012 Share Posted March 23, 2012 x2 on the tranny jack, it makes all the difference. That and a friend to help swear and push... B Link to comment Share on other sites More sharing options...
Trogdor636 Posted March 23, 2012 Share Posted March 23, 2012 They make adapters to turn most floor jacks into a tranny jack as well, never used one though so I cant speak for how well they work. Link to comment Share on other sites More sharing options...
JohnMasters Posted December 4, 2012 Share Posted December 4, 2012 (edited) Good Afternoon Npora... I was about to start a thread when I saw this one and I think this is a better place to start. I had a similar problem this week as the OP, however not as extreme, and was looking for some clarification as to what may have happened. I had been driving the truck then parked it for two hours and then started it up and the problem began. I was going up a very small incline and the truck would NOT go more than 10 or 15mph. Unlike the OP I had not spun the tires or been in any adverse conditions. It would just bog down and go nowhere and try to stall until it was allowed to go back to idle where it was working fine. I drove about 1/4 of a mile thinking that it would correct itself but it did not. Before calling AAA I thought I had at least turn it off and then back on in case this were some kind of limp mode as in my RX7. It did, in fact, re-start and I was able to drive it home on the highway at about 65mph. While on the highway I noticed a small bucking of the transmission very consistantly about every 20 seconds. After letting it sit for an hour I then took it to fill up the gas tank and add some fuel treatment thinking that maybe there had been some trash in the gas. I tend to drive around with a 1/4 of a tank or less which is probably not smart. The check engine light never illuminated. The truck is now running just fine with no bucking but I feel a bit uneasy about possibly getting stuck in the future and I have no idea what may have caused this situation. Before this...The truck has been running fine with no transmission issues. It has had a trans cooler for most of its life. It has 220,000 miles. I put on a new MAF harness a few months ago so the idle is a rock solid 750. Occasionaly I feel as though I smell gas at start-up and a few times I have felt a very small hesitation when just starting to accelerate but nothing to cause concern. Does this sound like limp mode and does anyone have any opinion about what may have caused it. Thanks in advance and BTW Olblue... Did you get your issue figured out? John Masters Edited December 4, 2012 by JohnMasters 1 Link to comment Share on other sites More sharing options...
silverton Posted December 4, 2012 Share Posted December 4, 2012 Yes, there is a limp mode and turning the vehicle off and restarting it after 30 seconds disables limp mode, I found this out one day while out on the trail, had me in a slight panic! And to deter you from pulling the engine and transmission out together, it is far easier to just drop the transmission. When you remove the engine, you also need to drop the front differential. Link to comment Share on other sites More sharing options...
Kingman Posted December 5, 2012 Share Posted December 5, 2012 I'm not sure why people are still stuck on the cooler clogging. That's not the problem. The problem is poor transmission design, but they still last longer than Nissan ever intended them to. Japanese vehicles aren't even meant to go past their first timing belt change on their island! But these transmissions go 170-200,000 miles before the trans let's go, even with routine maintenence. Because it is a major problem. Well, symptom actually... the poorly designed transmission spews a lot of clutch debris through the factory cooler and clogs it because of the fin style, then there is no flow at all and the transmission burns up completely. Link to comment Share on other sites More sharing options...
silverton Posted December 5, 2012 Share Posted December 5, 2012 There is only a tube inside the bottom tank that the transmission fluid goes through, it doesn't travel through any of the fins of the radiator. The only way to clog that is with a rock.... and you're going to lose a whole lot more than just a single gear! it's just a liquid to liquid cooler. There is never any blockage, only a transmission that lasts too long (for the japanese). Link to comment Share on other sites More sharing options...
Towncivilian Posted December 5, 2012 Share Posted December 5, 2012 Yeah, I never understood how that tube can get clogged. It seems implausible. Improper maintenance of the transmission is generally to blame, not a clogged cooler. Link to comment Share on other sites More sharing options...
Kingman Posted December 5, 2012 Share Posted December 5, 2012 I remember there being a TSB from Nissan back in the day that addressed the coolers clogging. It said to replace the radiator because with the design of the cooler they couldn't be cleaned when they clogged. When I replaced an auto on an '88 the cooler was fairly clogged with debris. I put an auto in an '03 Durango that had a factory cooler on it and it was clogged solid. The transmission that was in it was new already but burned up in a few thousand miles. Put a big ass cooler on it and it was fine. Link to comment Share on other sites More sharing options...
Precise1 Posted December 5, 2012 Share Posted December 5, 2012 There is never any blockage, only a transmission that lasts too long (for the japanese). Really? That's why time and time again people have found their cooler blocked? That's not why shops often replace the radiator (or bypass it) when they rebuild/replace the auto tranny? That's not why a dealership mechanic flushes the tranny cooler as a procedure or why Nissan has a product specifically to do this? http://www.nissanpat...ng/#entry597223 Remember, build up from the fluid heat exchange can reduce the diameter and cooling efficiency and create areas where sediment can adhere as well. Opinions are fine until they fly directly against years of data and misdirect people; don't be a Tungsten, dude... B Link to comment Share on other sites More sharing options...
Slartibartfast Posted December 5, 2012 Share Posted December 5, 2012 (edited) It's quite possible that the design of the cooler changed at some point. I'm pretty sure I've seen pics of the tranny cooler that just shows a little tube. One type may be more prone to clogging than the other, which would explain the wide difference of opinion. (edited, realized the pic I'd posted was of the wrong thing) Edited December 5, 2012 by Slartibartfast Link to comment Share on other sites More sharing options...
silverton Posted December 5, 2012 Share Posted December 5, 2012 That's the bottom tank of the radiator. Coolant runs through there, the tubes you see are where the transmission fluid is. And that doesn't look like a Pathfinder anyway, the outlet is not in the center, it's on the passenger side of the tank. That "mud" in there is just an improperly maintained coolant system., which will also reduce heat transfer from the transmission as it's building up on the heat exchanger tubes. I can justify sediment build up in the tube(s) that reduces the heat exchanged, but to say that the tube is blocked is wrong. If there is no flow, there is no go in an automatic transmission. Link to comment Share on other sites More sharing options...
silverton Posted December 5, 2012 Share Posted December 5, 2012 And I'll say again, the Japanese only intend their vehicles to barely last to their first timing belt change, we're lucky they make it to their second! They don't have the room to have junkyards around to keep their 20 year old junk running for 20 more years... haha Link to comment Share on other sites More sharing options...
Precise1 Posted December 5, 2012 Share Posted December 5, 2012 There are countless Japanese vehicles that have over 200 and 250k miles, and still run fine. I'll disregard your statement until you can back it with facts, not supposition. Now, lets get back on track with the thread... B Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now