3800Pro Forums banner
1 - 3 of 3 Posts

1 Posts
Discussion Starter · #1 ·
Hello! I’ve spent weeks and weeks searching for an answer to no avail so I figured I would post here as well.

I’m looking for a place where I can buy something like the 4t65e conversion kit sold on zzperformance (Gear Ratio Conversion Kit). Trying to get a 3.69 ratio for better low speed acceleration. Their one has been out of stock forever and I can’t find anyone else selling something similar and in stock aside from MMS who sells one for $2000.
Ideas? Car is a modded 2004 LeSabre with the following:

105lb valve springs
Steel Valve Spring Retainers
Custom pushrods
GT1 Camshafts
H-Body Downpipe w/ MagnaFlow Turbo XL muffler
Rollermaster Double Chain Timing Set
LS7 Hydraulic Roller Lifters
Extra thick front cover gasket
Machined oil pump cover
K&N drop in air filter
High flow fuel filter
Custom tuned PCM
180 degree thermostat

Right now 0-55ish is all 1st gear and then when it shifts to 2nd I’m getting a huge rpm/torque drop because all the gears are so long.

Any recommendations would be greatly appreciated!!

1,252 Posts
(Edit: my apologies... just got out of a rough training course, don't take the salty replies personally)

It's an OEM part from the older 4T60/60e transmissions from the early 90's. You can either hunt down a fresh set of sprockets/chain from a parts supplier (or local trans specialist shop), or find the right vehicle/trans code to get from a junkyard. Both of those have more than surface-level details involved to fully accomplish, but it's honestly up to you on how much you really want to go into it for a minor tweak that gets you from beating Civics from a stoplight to beating V6 Accords from a roll (i.e. performance isn't going to blow your mind N/A, and 3.69's are wasted on boosted cars... had 2 friends with it).

After finding the OEM sprockets/chain, the sprockets need machining to mate to our 65 system (details on that are somewhere, or a skilled person will recognize what's needed & be equipped to do it).

Sidenote: What's with all the recent LeSabre owners recently? Must be a bunch of original owner grandpa/ma's passed on after buying them 15-20 yrs ago.

844 Posts
local up here has a twincharged 03/04 lesaber

the 4t80e was available with a 3.71 FDR on olds aurora special packages, i have that 3.71 diff and a 3.11 on the shelf for the 442, both 80e's are currently 3.48

the *)e all reduction is at the diff planets so FDR changes are easy. the planet setction bolts to the diff....so even a heavy spring easy to overhaul posi is doable

the 65e requires both a chainset and a diff with the integral planets for the range of FDR available
1 - 3 of 3 Posts