PontiacBonnevilleClub.com

I recently visited the wrecking yard in search of an MN7 trans with FR2 ratio code. I DID find one, but it was in a Monte Carlo. Only problem is that it doesn't have the webbing that it's supposed to with SC engines. First I had my hopes up and wanted to get the unit, but after checking for the webbing my heart sunk and I was like

Can I use this unit or no? I hear that if the 4T65e unit doesn't have the webbing there it is suceptible to fracture. Need clarification here as I can be heavy footed at times and wouldn't want a broken case.

You ABSOLUTELY need a transmission case with the webbing. The W bodies (mote carlo) don't need it because they lack a rear trans or engine mount.

So how then does a Monte Carlo support its transmission? Tension arms on the front of the engine? Wonder if I ise a chain and latch down my engine that way.

Wonder if I could put a 4T80e in this car and call it good after having the ECM tuned to the respective ratio of the transmission I get. 3.11:1 would be my choice.

no the 80 is not a direct swap. While it would bolt up, you no need to make a brackets, and then have some one Tune it.

It would cost way more in the long run than to just get the correct 65

If only the 80 could swap in without any extra work... Yay for indestructo trans.

Why can't I just use the transmission out of the donor car that I have? It is a 2002 Grand Prix GTP. I know that the transmission will have a big pressure switch manifold but I am wondering if the computer can just swap over and it will work.

Did you miss the part about the W body Trans not have the webbing for the rear trans mount? The GTP does not have the structural webbing for the rear mount used on the H body..

The front of the H body does not have the support for the Dog Bones.. So I don't know what you would do there..

Spend a little now, or a lot later..

Maybe transfer the guts from one trans to another?

Jrs3800 wrote: Maybe transfer the guts from one trans to another?

Consider this. They are the same internally, except for the casing. Luckily all L67s got the 2.93 gearing.

This guy apparently did a 4t80e swap on a 3.8 ssei.

http://www.gmls4.com/index.php?topic=1015.0

That was on a '96 - '99, different mounts to begin with. Though the 4T80E did come stock in the Bonneville GXP, this is still way more then you want to tackle especially for a stock or even mildly modded L67.

Find a trans for you car to just drop in and go or rebuild your current one.

The 4T80 also needs some computer work to operate properly.

My trans code is FR2. What are the drive and driven sprockets tooth count? I might be getting a code thrown because of this be cause one of the codes reads illegal range. I don't know what the heck that means.