trans replacement..

350rs · 01-05-2010, 08:34 PM

im getting to the point where i fear the tranny may decide to no longer work.. Im wondering what the model is for the auto in a GT, and other possible doner cars. I cant find any GAs here in local salvage yards. So it may be something that i have to grab from another car. OR have the current one rebuilt. We have a very reputable shop down the street, but i havent priced it. Any ideas on cost to rebuild the current unit?

Its not that its acting weird really, other than the strange "hopping" around that i have a video of. But thats gotta play hell on various parts, not to mention my pride. ( what little is left with this car.

)

Tonyyank · 01-05-2010, 08:39 PM

4T40E is what it is i think

Grandamgtblk99 · 01-05-2010, 10:06 PM

4t45e in the GT

350rs · 01-06-2010, 03:23 PM

right on, thanks.

GrandAmMe · 01-06-2010, 03:32 PM

Quote:

Originally Posted by 350rs

right on, thanks.

The guy who is parting out like 10 GA's in the stuff for sale section is selling a tranny for $100!

01-06-2010, 03:32 PM

40 is in 4 bangers.

01-06-2010, 03:33 PM

nice good deal. replace convertor while your at it.

01-06-2010, 03:37 PM

check if it is out of a gt. all other 4t45e's have different final ratios. that may upset the computer a lil

GrandAmGTTT · 01-06-2010, 04:09 PM

Quote:

Originally Posted by hahano404

check if it is out of a gt. all other 4t45e's have different final ratios. that may upset the computer a lil

ya the tranny out of the SE has a slightly smaller gear ratio, but i'm not sure what you would need to do in order to make it run correctly

350rs · 01-06-2010, 06:35 PM

Quote:

Originally Posted by GrandAmMe

The guy who is parting out like 10 GA's in the stuff for sale section is selling a tranny for $100!

oh yea?! well ill have to have a look see

MIgrandamguy · 01-08-2010, 04:02 PM

as long as your get the tranny off the same motor, you should be fine as far as gear ratios go, i would assume.

See if you can find any Aleros in your local junkyard with your motor.

AaronGTR · 01-08-2010, 06:48 PM

Quote:

Originally Posted by MIgrandamguy

as long as your get the tranny off the same motor, you should be fine as far as gear ratios go, i would assume.

See if you can find any Aleros in your local junkyard with your motor.

Nope, the SE with the 3400 v6 has a 4T45E trans with a 3.05 final drive ratio and the GT with the 3400 v6 has a 4T45E has a 3.29 final drive ratio. Exact same engine and transmission, but different final drives.

If you buy a used trans from someplace, make sure they check the RPO codes on the car it came out of. If it has MN5 and FR9 in there, it's the right one. MN5 is for the 4T45E transmission and FR9 is the 3.29 final drive ratio.

lightningGA · 01-08-2010, 08:50 PM

just curious....what would have to be changed in the PCM to make it work SE -> GT or GT -> SE final drive ratio. Or is this something that can't be done with a Powrtuner?

350rs · 01-08-2010, 10:49 PM

going to check price on rebuild if i just drop off the car tomorrow. Ive asked this guy that same question about a few cars. Only a hour or two of labor. Only another 100 or 200 bucks? Ill spend that on the "new" tranny. So if thats the case ill just bring the whole car.

I think ive got a main seal leak which i can fix while the motor is out anyway.

burgett2103 · 01-08-2010, 10:53 PM

ok quick question i figured i'd throw in here.. does a 3800 supercharged gtp tranny fit up to our 3400 v6's?

350rs · 01-09-2010, 08:36 AM

i would imagine no. i think those have the same transbolt pattern as a standard SBC

AaronGTR · 01-09-2010, 09:11 AM

Quote:

Originally Posted by lightningGA

just curious....what would have to be changed in the PCM to make it work SE -> GT or GT -> SE final drive ratio. Or is this something that can't be done with a Powrtuner?

I haven't tried it myself, but I've looked into it because others have asked before. I know it can definitely be done. I'm just not sure exactly what has to be done. It basically depends on the speed output sensor. I don't know if the sensor ring has the same number of teeth for both transmissions or not. iirc it's on the output shaft right next to or on the differential. It's been a while since I looked at it. If they were a different number of teeth, you might have to switch it over to the new differential. If they are the same, which I think they are, then it would all be programming. Or it's possible that even if they are different, you might be able to simply make programming changes in the pcm and it would work just fine. I'm inclined to believe the later. The pcm uses the pulses from that sensor to run the speedometer, odometer, and for shifting under 100% throttle because shifting is done on a gradient based on throttle position and MPH. All that may be required is changing some of the shift tables for the trans and the pulses per mile table... or maybe just flashing the pcm with a complete program for the SE or GT depending on which trans you are using.

Basically though it shouldn't be as complicated as it sounds.

Quote:

Originally Posted by burgett2103

ok quick question i figured i'd throw in here.. does a 3800 supercharged gtp tranny fit up to our 3400 v6's?

Quote:

Originally Posted by 350rs

i would imagine no. i think those have the same transbolt pattern as a standard SBC

Actually, yes it will bolt to our block. The 3100/3400 block and 3800 block share the same bolt pattern. Both engine families have been bolted to 4T40/4T45 transmissions and 4T60/4T65 transmissions. The previous model grand am has a 3100 v6 bolted to a 4T60E.

Bolting a 4T65E-HD up to a 3400 is actually easy. It's making the custom mounts and axles and figuring out the electronics that is hard... but it can and has been done.

350rs · 01-09-2010, 11:32 AM

really? hm, maybe its the 4.3 thats got the SBC pattern then. i cant remember.

oldschoolguy · 01-09-2010, 11:34 AM

@AaronGTR you should write a book with everything you know about grand ams.

Seems like no technical question gets past you

AaronGTR · 01-09-2010, 09:28 PM

most of it comes out of a factory service manual, or just from trolling these forums for years and years. There are certain topics I don't answer though, mostly because I either haven't looked up that particular thing, or it's one that has been beat to death and I don't feel like helping out someone who doesn't bother to search.

Tom, it probably was the 4.3 vortech V6. That engine was based on the chevy v8. It's basically a sbc with two cylinders chopped off.

01-05-2010, 08:34 PM	#1
350rs GAGT - Member AKA: Tom Join Date: Mar 2008 Location: St. Louis, MO Age: 33 Posts: 547 Vehicle: 01 GT, 89 L98 Camaro	trans replacement.. im getting to the point where i fear the tranny may decide to no longer work.. Im wondering what the model is for the auto in a GT, and other possible doner cars. I cant find any GAs here in local salvage yards. So it may be something that i have to grab from another car. OR have the current one rebuilt. We have a very reputable shop down the street, but i havent priced it. Any ideas on cost to rebuild the current unit? Its not that its acting weird really, other than the strange "hopping" around that i have a video of. But thats gotta play hell on various parts, not to mention my pride. ( what little is left with this car. )

01-05-2010, 10:06 PM	#3
Grandamgtblk99 Burgee AKA: Allen Join Date: Mar 2006 Location: Orange, Tx Age: 39 Posts: 787 Vehicle: 1999 Grand Am Gt	4t45e in the GT __________________ 1999 Sc/t turbo.

01-08-2010, 08:50 PM	#13
lightningGA Bagged and Boosted!! AKA: Paul Join Date: Aug 2002 Location: Saratoga, NY area Age: 47 Posts: 1,424 Vehicle: Boosted 00 GA	just curious....what would have to be changed in the PCM to make it work SE -> GT or GT -> SE final drive ratio. Or is this something that can't be done with a Powrtuner? __________________ CARDOMAIN Not updated in forever!!! XCLUSIVE Car Club Eaton SUPER CHARGED!!!!!

01-09-2010, 09:28 PM	#20
AaronGTR BlingWithBallz AKA: Aaron Join Date: Aug 2002 Location: Detroit area, MI Age: 43 Posts: 12,254 Vehicle: 2000 Grand Am GT1 2dr	most of it comes out of a factory service manual, or just from trolling these forums for years and years. There are certain topics I don't answer though, mostly because I either haven't looked up that particular thing, or it's one that has been beat to death and I don't feel like helping out someone who doesn't bother to search. Tom, it probably was the 4.3 vortech V6. That engine was based on the chevy v8. It's basically a sbc with two cylinders chopped off. __________________ The few, the proud, the boosted! 13.788 @ 103.73 mph (3/2011) 320 whp and 300 ft/lbs torque. (3/2011) See it here. the total package.

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

01-05-2010, 08:39 PM	#2
Tonyyank Administrator AKA: Anthony Join Date: Aug 2002 Location: Parma, MI Age: 40 Posts: 3,470 Vehicle: 09 Silverado 4x4	4T40E is what it is i think

01-06-2010, 03:23 PM	#4
350rs GAGT - Member AKA: Tom Join Date: Mar 2008 Location: St. Louis, MO Age: 33 Posts: 547 Vehicle: 01 GT, 89 L98 Camaro	right on, thanks.

01-06-2010, 03:32 PM	#6
hahano404 Guest Posts: n/a	40 is in 4 bangers.

01-06-2010, 03:33 PM	#7
hahano404 Guest Posts: n/a	nice good deal. replace convertor while your at it.

01-06-2010, 03:37 PM	#8
hahano404 Guest Posts: n/a	check if it is out of a gt. all other 4t45e's have different final ratios. that may upset the computer a lil

01-08-2010, 04:02 PM	#11
MIgrandamguy GAGT - Newbie AKA: Phill Join Date: May 2009 Location: MI Posts: 11 Vehicle: 2004 Grand Am GT Coupe	as long as your get the tranny off the same motor, you should be fine as far as gear ratios go, i would assume. See if you can find any Aleros in your local junkyard with your motor.

01-08-2010, 10:49 PM	#14
350rs GAGT - Member AKA: Tom Join Date: Mar 2008 Location: St. Louis, MO Age: 33 Posts: 547 Vehicle: 01 GT, 89 L98 Camaro	going to check price on rebuild if i just drop off the car tomorrow. Ive asked this guy that same question about a few cars. Only a hour or two of labor. Only another 100 or 200 bucks? Ill spend that on the "new" tranny. So if thats the case ill just bring the whole car. I think ive got a main seal leak which i can fix while the motor is out anyway.

01-08-2010, 10:53 PM	#15
burgett2103 Sounds for Dayzzz AKA: Nick Join Date: Dec 2008 Location: Tonica, IL Age: 30 Posts: 1,886 Vehicle: 03 GAGT/98 Chevy 1500	ok quick question i figured i'd throw in here.. does a 3800 supercharged gtp tranny fit up to our 3400 v6's?

01-09-2010, 08:36 AM	#16
350rs GAGT - Member AKA: Tom Join Date: Mar 2008 Location: St. Louis, MO Age: 33 Posts: 547 Vehicle: 01 GT, 89 L98 Camaro	i would imagine no. i think those have the same transbolt pattern as a standard SBC

01-09-2010, 11:32 AM	#18
350rs GAGT - Member AKA: Tom Join Date: Mar 2008 Location: St. Louis, MO Age: 33 Posts: 547 Vehicle: 01 GT, 89 L98 Camaro	really? hm, maybe its the 4.3 thats got the SBC pattern then. i cant remember.

01-09-2010, 11:34 AM	#19
oldschoolguy noob AKA: huh?? Join Date: Apr 2009 Location: BC Canada Posts: 510 Vehicle: '01 Grand Am	@AaronGTR you should write a book with everything you know about grand ams. Seems like no technical question gets past you