4t60-e fdr

[kprofthestrs]

in the fdr discussion article here 60*v6 the article states for a 3.73 fdr you need the 33/37 chain gears question being are these gears the same as the 37/33 chain gears in other trans. meaning are the same gears or do they mount differently?

[gectek]

i think that if you change the gears you also have to change the input shaft speed sensor, since it would read wrong. and the best way to tell if they are the same parts would be to call the dealer and have them look. if the 4t60 is a newer style like 95 and up, i can look at the p/ns and see if they are the same. what other sprockets from other transmissions are you looking at?

[kprofthestrs]

i know i need the 3.33 gear ratio. most of those were in the w bodies.
and the chain gears. this is the original trans out of my car that i removed when i chaged over to a 00 3400 and a 96 transmission for lower milage. i'm going to rebuild the original and reinstall it using heat treated parts and probobly kevlar clutches.

[Azrael]

You'd have to modify the ECM tuning for the new FDR or it'll throw a code when it sees that the engine RPM isn't matching axle RPM (via VSS) the way it expects.

As for the gears being reversable, if GM's penchant for being a pain in the ass has never faultered, then the drive and driven gears will be slightly different in some way. I remember this being asked before but it was never answered.

[kprofthestrs]

hopefully before the trans is done ill have installed the megasquirt system
into the vehicle to help that concern since its a obd 1.5 pcm.

[gectek]

well even the 3.29 gears(4t45e) arent all the same, some have a reverse pitch, so you just have to get the ring gear, sun gear and FD, but let me see if the #s are the same on those for the year models

ok for the 4t60(440t4) it shows 3 diff chain drive ratios, 35/35, 33/37, 37/33, those are for 83-92 and also 3 diff FDRs in the 3.33, large pin, and 2 small pins, 1 with 20 teeth and speedo/large bore reluctor, the other is without the reluctor, large pin is 83-88 and the small pins are 88 and up,

on the 4t60e and 65/hd is shows 4 separate chain drives, one roller chain, one rocker chain style, one 7/8 wide roller style(for riviera only) and 1 gemini(double roller) design. the double roller is in the 4t65 for 97 and up. the roller style is in the 91-93. the other two rollers are still used from 95 and up. also the prockets are the same for 91-92 and the same for 93 and up, the only way to interchange them in the 97 and up trans is to use the shaft from the 97 and up. but the 97 and up can be used on the 93, you just have to switch out the turbine shafts on the 97 and up for the 93...that way you can have a double roller set in a trans earlier than 97.

on the final drive there are also 2 different pitches on the gears, one is standard pitch, one is fine pitch. the fine pitch do not come in a 3.33 gear, only the standard do. but the 3.33 are all the same pitch for 91 and up AFAIK. also there are 2 diff reluctor rings a 30t and a 31t but i think that pcm programming will correct the signal, since there is only 1 sensor for output shaft, but 2 designs (1 long 1 short) the standard pitch FD has a 70t ring gear, the fine has a 78T ring gear, ring gears must also match the forward drum(same from 91-95 and same from 96 up)

also there are 2 diff designs of ring gear, for the standard pitch, 91-95 1st design, 96 up 2nd design

hope that helps...basically anything 96 and up will work on anything, with hard parts, but the 91-95 stuff will have to be looked at closely when swapping with 96 and up stuff, but it CAN be done, just takes a few other swapped parts. i think thats all for now, but if you run into problems, i may have more info

[3400-95-Modified]

I didnt fully read this, but NO you can not swap gears, one holds the hub for the 4th clutch pack.

Second you do NOT need to swap any speed sensor because your speedo will still read correctly since the speed is picked up right on the diff carrier, its not picked up before any gears. BUT yes your car will probably throw a code, My OBDI.5 did NOT throw a code when I went to 3.33 gears, I found that odd... yet when I did my OBDII swap it threw a transmission component slip code.

What transmission are you starting with from what car and year, I will tell you what you need to go get to make what you want.

[gectek]

well srry didnt mean swap the gears in leterally, i meant the swapped ratios

also i think the speedo will run diff if you use the 31 tooth over the 30 tooth it shouldnt be much off, but you can always swap the reluctor gears on the carrier just to make sure, they are the same dia.

i guess you wont have any probs with the 4t60 like the 4t45 because the 45 has diff input speed sensors, and the 4t60s dont(??) but the 65 does, or at least thats what i show

[3400-95-Modified]

4T60E has a speed reluctor on the case of the diff, so when gear ratios change nothing is changed speed wise since the reluctor is basically driven off of the axle speed.

As far as changing ratios, you do not HAVE to change your diff. I wanted 3.33 gearing and everyone told me I needed to get the drive and driven gears and the diff and sun gear from a 3.33 donor since my car was 2.97... What they don’t realize is the 1994 2.97 tranny already has a 3.33 diff so all I needed to change were my drive driven combo from 37/33 to 35/35.

3.73 on the other hand is very aggressive gearing even using a 1996 Beretta tranny you could obtain a 3.68 FDR with the 33/37 combo and the stock Beretta 3.29 diff.

This is why I say tell me what you have because most likely you can get very close to the 3.73 with ONLY the drive and driven gears getting swapped. Unless you have a crazy 3.05 diff which wasn't used on L&N bodies, but then again I don't know what your starting with.

gectek I wasn't referring to you when I said no you can not swap gears, I meant the first few posts when they were asking if drive and driven were interchangeable.

[gectek]

well yah you can get the diff drive from the chain, no prob on that, i was just showing what the different options were, srry i went too in depth and lost the point, you can get alot of diff ratios from just changing the chain drive using the same diff.

plus there are a few driveability concerns with going too agressive on the FDR or chain drive for that reason, it will change the gear ratio of every gear, leading to diff fuel ecomony ultimately and maybe even bad performance if the engine is not kept at a good power band range

[sharkey]

i guess you wont have any probs with the 4t60 like the 4t45 because the 45 has diff input speed sensors, and the 4t60s dont(??) but the 65 does, or at least thats what i show

the 4t60 (also known as the 440t4) wouldnt have that issue becuase its not electronicly controlled. the worst you may have to do is change the govener drive gear.

[gectek]

yah i wasnt talking about the 440 in that one, it wouldnt have many sensors anyway since it is mainly hydraulic...ill bow out of the rest of the in depth in this