GEN IV (AFM, flex fuel) into '97 2dr 4wd Tahoe

[harascho]

my Tahoe conversion is getting a little shape these days. The engine is still in a container somewhere on the Atlantic... but I have enough other parts to
play with.
For those who forgot:I am converting a 1997 2dr 4wd tahoe to an '07 drive train, engine 5.3 "LMG" with flex fuel and AFM.

Here are some pics of the work..


The Tahoe has already lost it's old engine and tranny



work will involve a cleanup , degreasing and rustproofing the engine bay, frame rails



parts of the '07 harness laid out



most of the '97 parts are in bins and were stored for a while..


'97 radiator with '07 Avalanche e fans



they fit without problems.. only two small U-shaped brackets to the plastic side tanks and we are ready to go.. best thing, the fans cost only 150bucks....

'07 cluster and DIC switch
engine bay fuseboy lower part with connectors
BCM and engine fuse box




as I am working together with PSwired ( who has similar problems ...)
we are able to push each other through the little " I don't know's.."

Ok... Friday and Saturday passed by and I could not start with the wiring. I was busy with cleaning the engine bay and frame rails. There is nothing worse as removing rust with a wirebrush on the grinder and a piece to clean like a Tahoe's frame..

My back hurts, my finger hurt but the work is done... My son Marvin gave me a hand when it was painting time..( I told him the Tahoe will be his when he is old enough..that was a good motivation..)



engine bay painted



The fuse box on the driver side needs the antilock controller to be moved slightly downward. I had to modify it's bracket and it seems all will fit in almost the original positions.... we will see when the paint is dry.
modified antilockctrl mounting bracket



I hope the sunday brings some time for the wiring...

I checked for space to get the '07 battery tray and underhood fusebox in the proper location. The battery tray on the passenger side could be fittet with some additional brackets.

[harascho]

This weekend I could make some progress... I got my hands on all the small problems... As I want a close to factory look I opted for all the original brackets...

So the first problem was the battery tray on the passenger side, close to the windshield... I had to cut the inner fender to create a platform deep enough for the battery..






next I have to sort out the wiring. I have to shrink the '07 harness down to the point of wires I need...



next is fuel tank... I Patrick gave me a hint with a sealer which will make my mild steel gas tank E85 resistant




then the '07 fuel pump module and the '97 gas tank... its clear that won't fit without some modifications...





after that when the engine will be in the Tahoe I will have to built a Y-pipe out of this stuff..



ok.. sunday afternoon.... is there a better time to sort out some wirng issues??

[harascho]

ok, the weekend brought some progress.
To prepare the engine bay for my swap ( '07 GEN IV " LMG" into '97 2dr Tahoe) lots of things had to be changed. The antilock hardware is now positioned more downward the inner fender to make room for the '07 engine fuse box,
the Chevy toolbox on the driver side had go in favour for the ECU/TCM bracket.




On the passenger side the inner fender had to be modified to form a flat platform for the battery tray. In front if this the '07 coolant expansion tank will be mounted.




Then the '07 Avalanche fans. The pastic recieved some trimming. Then a piece of flat steel was welded in front of the lower radiator mountig platform. The e-fans have two C-shaped brackets that fit into that new crossbar.




On top the original radiator mounting brackets where extended 1" .





Between those new brackets an aluminum 90 degree angle was fittet. It mounts to the modified radiator brackets with four 8mm bolts and the e-fans are bolted to that angle.




All in all a tight (especially on the steering box side..) but sweet OEM looking fan setup.





And the best thing is the E38 ECU of the GEN IV engine controls the fans.

[harascho]

Hi guys... some progress on my side in the past days.

I have the new 5.3 flex fuel / active fuel management in my Tahoe's engine bay...



I used the common adaptor plates to switch from the new 4 bolt to the older 3 bolt engine mount style.



I must admit the engine slipped into place with only a slight massage on the rubber mounts necessary.


yesterday I bolted the transfer case to the new 4L60E ( Why didn't I go for the 6L70 as Patrick did?? I really don't know..)


Then all is prepared to bolt the tranny to the engine.
I am curious of all lines up in the old positions, I will know in a few hours..



I also removed the dash. I have to modify the dash to accept the '07 instrument cluster.. I did a short testfit and I think I can do it in a way that the whole setup looks good.







A lot of the under dash wiring will be cut out and replaced by the '07 harness.
Lots of circuits are different now, cause in the '07 trucks the BCM controls most of the functions as exterior lights, turn signals ignition switch and the related power states of the truck. I built a small adaptor box in which I stuffed all the necessary circuits to adapt the '97 logic to the '07 logic, for example the headlights... in the OBS trucks the electric load is switched by the headlight switch (it switches 12V from a fused batt source to the lights..) lots of current flows over the switch contacts.. in '07 the headlight switch just grounds some BCM inputs and the BCM switches the correct relais in the engine compartment fuse box. Another benefit is the bulb fail management of this new setup... you will have a message in the instrument cluster when a bulb fails..

[harascho]

This time the exhaust was on my list:

y_pipe news...

I did some welding and pipe cutting yesterday... Why did nobody try to built a bigger y-pipe where the two pipes meet somewhere behind the transfer case?
In this way you will have access to the tranny pan. Only drawback is to remove the y-pipe you have to remove the tranny crossmember first. But how often do you remove a Y-pipe??










Only thing I had to do is to cut out two of the O2 sensor flanges and weld them behind the left and right cat.

This was yesterday late afternoon. It was not planned that after drilling the hole for the first o2 sensor, that the cat heatshield cut through my finger.... ok the doc in the hospital stitched all tohether...
But that will mean electric wiring for this week... no heavy parts or wrenching....

[NITROUS]

Looks great! Keep us updated, this is a nice project...................

[bigburb]

awesome project. is that the stock radiator? it looks like aluminum. I've got a crappy coated copper radiator that is starting to oxidize.

[harascho]

yes it's the stock radiator of the 1997 Tahoe

[GasGuzzler]

awesome project. is that the stock radiator? it looks like aluminum. I've got a crappy coated copper radiator that is starting to oxidize.

I don't remember what year your truck is but it was common in 92-93 for the dealers to remove the aluminum and plastic radiator and replace it with a copper/brass unit due to tank problems. Eventually GM got to where the cheaper and lighter new style radiators hold together for at least 100K+ miles in most cases. Cheaper and lighter isn't always true as a 2500 series 34" 4-core for an 88-98 is $800.00 from GM.

[00shortbox]

Nice looking project man, it's coming along nice! Looking forward to seeing the rest of the progress.