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Discussion Starter #1
I have a couple questions about my tahoe and didnt know if yall could help.

1. How do I tell if I have 3.73 or 3.42 gears? Truck is 4wd with a tow pkg, I think.

2. How do I tell if I have the tow pkg?

3. How hard is it to change out the trailer plug from a 4way to a 7 way round?

Vin#1gnek13r4xj493080
Model#k10706

Thanks.

ALB
 

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I have a '97 Tahoe 4dr 4WD w/ tow pkg and I just had rear end rebuilt. Asked shop to let me know gears and they confirmed I have 3:42. At 2000 rpm, I'm running about 77.5 mph. Under 2100 at 80. If you are about the same, then you have 342s.

The Tahoe is NOT prewired for 7 wire. You will have to run a single wire from the controller you install to the plug. The hardest part for me was to find the wire that goes to the "cold" side of the brake switch. That wire is like 22ga (super small). Getting my probe pushed through the insulation to test was a major pain! BTW, iirc, it's a white wire in a different loom than you initially look at. WWAAAAYYYY up under the dash. It's best if you are a contortionist!

Do NOT believe the owner's manual! DO NOT tow in O/D!!!! It will eventually kill the transmission. I put 2 in mine. Now I have the Duramax for all my towing needs!
 

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You have a tow package if you have a transmission cooler in front of your radiator.
 

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hows your package

You have a tow package if you have a transmission cooler in front of your radiator.
usually an engine oil cooler, 3.73 gears, tranny cooler as stated and factory run wires to the back a stealership should be able to tell you by vin code
 

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Discussion Starter #5
Thanks. I'll check but I believe I might have the 3.73s because with cruise on 70mph I am already @ 2000rpms. I'll have to double check.

I was wondering how big a pain it was going to be to switch to the 7 way round plug. I am not putting a brake controller on the truck just want to switch to the round plug for the trailers I do pull. I NEVER tow anything over 2000lbs in OD, always D. My dad and I found that out the hard way with his 94 Suburban and melted the tranny @ 80k. My Tahoe has 176k on the original tranny and still shifts smooth because I have taken care of it.

Definately getting a Dmax for heavy towing but for the loads I tow now with the Tahoe, she'll pull just fine.

Thanks again and I will let you know what I come up with. Have a friend at the stealership so I will ask him to run the VIN.
 

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EASY to tell if you have 3.73's. Open the glove box and look at all the 3 letter codes on the bottom o fthe box. There will be one that starts with a G... if it's GT4 then you have a 3.73 gear ratio. If it's GT3, then thats 3.42. Also, if you see G80 then you have the G80 rear locker (you probably don't though). As for the tow package, not sure how to tell. If you have a reciever hitch and a tranny cooler then you probably have it, since thats about all it is. And if you don't have a tranny cooler (one in front of the radiator, not just the lines that run into the radiator) then do yourself a favor and buy one!! As you have found out (I did too) heat will smoke those weak trannies in the tahoe's and halfton's. I put a cooler and tranny temp gauge on my old truck and never had a problem after that.
 

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If all you want to do is put the 7 pin RV trailer plug and only have the lights, then it won't be hard at all. Mount the bracket (mine is welded to the receiver frame), and use wire connectors to connect the 4 wires to the appropriate pins on the RV plug.

Alternatively, you can build a cable with the 4 pin trailer side plug and the 7 pin truck side plug that will do the same thing. Use this as an adapter so you can tow trailers with the 7 pin connector behind your Tahoe that has the 4 pin.
 

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Discussion Starter #8
If all you want to do is put the 7 pin RV trailer plug and only have the lights, then it won't be hard at all. Mount the bracket (mine is welded to the receiver frame), and use wire connectors to connect the 4 wires to the appropriate pins on the RV plug.

Alternatively, you can build a cable with the 4 pin trailer side plug and the 7 pin truck side plug that will do the same thing. Use this as an adapter so you can tow trailers with the 7 pin connector behind your Tahoe that has the 4 pin.
I do want the lights but I also want to be able to disengage the surge brakes on the trailers I tow. I know that a wire has to be connected to the reverse lights to trigger the solenoid on the trailer to disengage the brakes for backing up.

I dont need a controller for that do I?

Thanks GR8SHOT, I will check that out.

ALB
 

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I have never dealt with surge brakes, only electric brakes, so I don't know. Sounds doable though.
 

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Discussion Starter #10
gr8shot, we have a winner.

I do have the GT4 and G80 codes so I do have 3.73 gears and the limited slip. I also do have the cooler infront of the radiator.

Thanks for help guys.

ALB
 

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Nice!! Looks like you got a good one! 3.73, locker and tow package! You're pretty much as set as you can be other than the 7 pin connector!!
 

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Discussion Starter #12
Nice!! Looks like you got a good one! 3.73, locker and tow package! You're pretty much as set as you can be other than the 7 pin connector!!
Thanks!!! And I just picked that up!. Question now is where in the hell do I mount it...:rof:help

There is no good spot to...:confused:

ALB
 

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As I said, mine is welded to the left half of the hitch. Sorry no pic and the truck is back home.
 

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Discussion Starter #14
Got it installed. Bolted it under the flat of the bumper just to the left of the license plate and in front of the hitch. Looks good and the wires were easily ran. With this truck, they have a regular 4 wire harness AND an 8 wire harness for this application.

I will get some pics and post them tomorrow. When I get my Dmax, this truck will probably be kept as a 2nd vehicle.

Guess putting a Dmax in my tahoe would be crazy!?!?!?!?!?!

Thanks again for the help.

ALB
 

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Gr8shot was right with the gt4 being 3:73, but gu6 is 3:42.
 
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