xtremerevolution Posted December 17, 2009 Report Share Posted December 17, 2009 Well after researching a bit I see that the 4 gear spline has a nice habit of shearing to the point where it is completely smooth. Awesome. Guess I'll get the car over to a mechanic that I know and see if we can manually engage fourth gear. If not, looks like it'll be time to bust out some $$$/ At this point I would consider the price of a transmission rebuild and compare that to the price of an L67 swap. I know if I have to pull my engine to fix the transmission, I'll just put in a low mileage L67 and be done with it. his car already has the l67 Doh! nevermind Quote Link to comment Share on other sites More sharing options...
jeremy Posted December 17, 2009 Report Share Posted December 17, 2009 he says it's his 99 Regal GS Quote Link to comment Share on other sites More sharing options...
Andrew Posted December 17, 2009 Report Share Posted December 17, 2009 i just got back from driving my GTP on the highway. in 3rd, i run around 2700rpms @65mph. cruise on, im around 1800-1900. Quote Link to comment Share on other sites More sharing options...
ZeeQuick Posted December 17, 2009 Author Report Share Posted December 17, 2009 Hehe, 1999 Regal GSE to be exact...that just turned 160,000 miles Thanks for running that little experiment Independent.....I'm jealous of you having 4th gear. If it does turn out to be the 4th gear spline, what really is the harm of just leaving it the way it is? The car (while I really like it) is just my winter beater, and while it bugs the hell out of me to not have a car in tip-top shape, I just assume save the $1000 or so and drive it as is. I really only drive the highway once a week or so, and according to the DIS my MPG is still at around 30mpg even at 2500rpm. I can see the point of just getting it done with now and then not having to worry about anything, as hypothetically that bullet-proof 3800 should steer me north of 200,000 miles easily. But I'm buying a house in the next month or two....and every $1000 counts. Quote Link to comment Share on other sites More sharing options...
Andrew Posted December 17, 2009 Report Share Posted December 17, 2009 it'll be fine, though i really dont see you getting 30mpg highway running that high of rpms. you can get a used trans for $200ish. Quote Link to comment Share on other sites More sharing options...
AL Posted December 17, 2009 Report Share Posted December 17, 2009 4th gear is the overdrive gear which if you disabled the TCC and had 4th gear, you would be running around 2100 rpms Quote Link to comment Share on other sites More sharing options...
AL Posted December 17, 2009 Report Share Posted December 17, 2009 Tcc is od... No, 4th gear is an overdrive gear, The TCC locking up is just making it a direct drive from the flex plate to the transmission input shaft Quote Link to comment Share on other sites More sharing options...
xtremerevolution Posted December 17, 2009 Report Share Posted December 17, 2009 Tcc is od... No, 4th gear is an overdrive gear, The TCC locking up is just making it a direct drive from the flex plate to the transmission input shaft I didn't know overdrive was a specific gear. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted December 17, 2009 Report Share Posted December 17, 2009 4th gear is the overdrive gear which if you disabled the TCC and had 4th gear, you would be running around 2100 rpms i wouldn't say a rock solid 2100... with the TCC able to slip, it could be 2300 with heavy throttle and 1900 light.... example numbers obviously, but when the TCC in unlocked, it's pretty damn variable Quote Link to comment Share on other sites More sharing options...
AL Posted December 17, 2009 Report Share Posted December 17, 2009 On FWD vehicles its a little different but I can explain it with a 4 speed RWD example, 1st gear is called maximum reduction (usually something like 3:1 gear ratio), 2nd is minimum reduction (usually 1.9 or so gear ratio), 3rd is direct drive which used to be the final drive on older transmission because it is a 1:1 gear ratio because the input and output shafts are directly connected, 4th gear is usually .8:1 ratio, called overdrive because the output shaft is spinning faster than the input shaft. The torque converter transfers the power from the flexplate to the transmission input shaft by basically forcing fluid to spin inside it, turning the other half of the torque converter, but that is only about 90% efficient... Inside the torque converter, there is a stator which when engaged, will lock both the drive side (turbine) and the driven side (impeller) together making it 100% efficient... Hope that makes sense, I just passed automatic transmission theory class yesterday so this is all still fresh in my mind. Quote Link to comment Share on other sites More sharing options...
Night Fury Posted December 17, 2009 Report Share Posted December 17, 2009 I finally almost get it! Quote Link to comment Share on other sites More sharing options...
AL Posted December 17, 2009 Report Share Posted December 17, 2009 What do you need me to explain? Quote Link to comment Share on other sites More sharing options...
Night Fury Posted December 17, 2009 Report Share Posted December 17, 2009 Hmm. I guess how can the output be spinning faster than the input in 4th gear? I get everything else. 1->2->3->4->4locked Quote Link to comment Share on other sites More sharing options...
AL Posted December 17, 2009 Report Share Posted December 17, 2009 Because of the gear ratio... Lets say its .9:1 ratio, That means the input shaft only rotating 90% of the way around for every time the output shaft makes a complete revolution... It can do that because the vehicle is already going about 40 mph or so and has alot of momentum behind it keeping it moving... And your engine isnt worried about getting the car up to speed where it needs to use alot of horsepower... In 4th gear, your normally cruising which takes very little horsepower and so the engine doesnt have to rev that high to keep the car moving... And they make the gear ratio accommodate for that... Hope that explains it a little better Quote Link to comment Share on other sites More sharing options...
Night Fury Posted December 17, 2009 Report Share Posted December 17, 2009 Yep. got it! Quote Link to comment Share on other sites More sharing options...
BXX Posted December 18, 2009 Report Share Posted December 18, 2009 So if the trans is crap, you can sell it to me cheap or trade me! Im in Parma 5 days a week at work if you wanna come check out my Cutlass.. It has 4 working gears and TCC works Just, well, its no L67 Quote Link to comment Share on other sites More sharing options...
ZeeQuick Posted December 18, 2009 Author Report Share Posted December 18, 2009 So if the trans is crap' date=' you can sell it to me cheap or trade me! Im in Parma 5 days a week at work if you wanna come check out my Cutlass.. It has 4 working gears and TCC works Just, well, its no L67 [/quote'] Haha, thanks for the offer.....hows $3500 sound?? Talked with a guy at a local transmission shop, who immediately agreed that the spline is probably stripped, says he sees it all the time on these transmissions. Told me to stay out of D and just drive it in 3, or he'd rebuild it for $1400 total. A used one for $200 wouldn't be bad, but with the frequency that these things break, I could conceivably find myself in the same situation rather quickly. Quote Link to comment Share on other sites More sharing options...
BXX Posted December 18, 2009 Report Share Posted December 18, 2009 Lol, $3500, no thanks. I see too many dealers having nice ones for that price with 100K and working transmissions Yeah, if your gonna keep the car for a decent amount of time, I would have it rebuilt and with plenty of new hard parts that are common to break as well. Maybe do a few upgrades to the trans as well when its being rebuilt? Quote Link to comment Share on other sites More sharing options...
Andrew Posted December 18, 2009 Report Share Posted December 18, 2009 $1400 is a decent price for the rebuild, assuming that includes all labor. install a new converter while you are at it. Quote Link to comment Share on other sites More sharing options...
ZeeQuick Posted December 18, 2009 Author Report Share Posted December 18, 2009 Haha, tranny works fine....3-speed....keepin' it old school Yeah, I'm weighing my options. I called one of the used parts places around here to inquire about another transmission, and he says he knows a few guys who have been driving these cars around without 4th gear for years. But if I do a rebuild, I will certainly be upgrading whatever I can to make that thing as bulletproof as possible. Learned that lesson years ago when I had the T56 rebuilt in my Z28. Quote Link to comment Share on other sites More sharing options...
BXX Posted December 18, 2009 Report Share Posted December 18, 2009 Haha, tranny works fine....3-speed....keepin' it old school Yeah, I'm weighing my options. I called one of the used parts places around here to inquire about another transmission, and he says he knows a few guys who have been driving these cars around without 4th gear for years. But if I do a rebuild, I will certainly be upgrading whatever I can to make that thing as bulletproof as possible. Learned that lesson years ago when I had the T56 rebuilt in my Z28. A decent pullapart trans might be worth a shot for the like $80 its gonna run tops. Can use your old one to build up when the funds are available.. Quote Link to comment Share on other sites More sharing options...
Andrew Posted December 18, 2009 Report Share Posted December 18, 2009 But if I do a rebuild, I will certainly be upgrading whatever I can to make that thing as bulletproof as possible. Learned that lesson years ago when I had the T56 rebuilt in my Z28. You can spend a ton of money on upgrades. http://www.zzperformance.com/grand_prix/products1.php?id=150&catid=105 Quote Link to comment Share on other sites More sharing options...
ZeeQuick Posted December 19, 2009 Author Report Share Posted December 19, 2009 Here's the thing though, if I'm just coasting and have it in 3, the revs stay up, as its forced into 3rd gear. If I throw it into D while coasting the revs go down to right around where they should normally be for coasting at a given speed. What does the transmission do when you are just coasting and in D? Is it not really in a gear at that point, more like in neutral? Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted December 19, 2009 Report Share Posted December 19, 2009 this help? Quote Link to comment Share on other sites More sharing options...
AL Posted December 19, 2009 Report Share Posted December 19, 2009 Inside the transmission is a one way clutch, freewheels one way and locks the other way... When in gear and you step on the gas, it locks and puts the power to the axles... When you let off and coast, it just freewheels allowing your engine to basically idle while the car is coasting... You have 2.89 gear ratio in your car and I have 3.29s so my rpms will be different but when I coast at speeds above 60, my rpms drop 500 below what they would be when I am cruising... For example, If I am doing 75, my tach says my rpms are at 2500 (my tach reads 200 rpms high) and I let off the gas, it will drop to 2000 rpms and will continue to drop with the related speed... Also, when you let off the gas or tap the brake when cruising, watch for your rpm gauge to jump up about 200 rpms or so before dropping, if it does, you know that your TCC is working and the TC is locking up because it can and will lock up in 3rd gear Quote Link to comment Share on other sites More sharing options...
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