I need my head examined, seriously...

[john8662]

I bought a 6.5!

1996 2 Door Tahoe 4x4 6.5L

Pulled it back with my '86 Banks 6.2L, did an impressive job, 14mpg pulling 70mph in overdrive the whole way, round trip ~725 miles.

Pic:

http://www.thedieselpageforums.com/photopost/data/503/medium/P1010008b.jpg

This will make a good replacement to add to the truck family, signature updated.

This thing is Virgin, lots of needed mods.

It's got HO cooling mods already, but needs HELP in the exhaust and intake area.

The first mod of course will be to KILL the EGR crap! Then kill the kitty, replace the ECM (part of the EGR delete), new glows... yada yada yada.

I spent the weekend doing the service that was needed. Dropped the 4L80E pan and serviced the tranny, then engine oil (with a flush), new serpentine belt, ditch the wally world Neverstart batteries (even though they work, I hate em). Need to go through everything else...

Didn't give too much for it, so I can't expect too much from it, but it's something to play with...

[ToddMeister]

How many miles on the 96, John?

Your plans are on the right path, Kill EGR,
Gut the cat right away, it'll breath a lot better.

[arveetek]

Cool man!

I love my '95! It's a joy to drive. You're right about the stock setup being gutless, though. I can't believe at the difference between my modded 6.2L and stock 6.5L. I'm pretty sure the wastegate is not operational, however. I need to order some guages to see what's really going on. I'll probably add a Turbomaster as well.

After fixing the OPS and installing a remote PMD, my Tahoe runs and drives like new, even with nearly 200K miles on it.

Have fun with your new toy!

Casey

[john8662]

103k miles on the '96.

It needs a good cleaning, hood needs to be repainted due to scratches. I may even add a white stripe to the side and make it a "candy cane" too.

I can't hear the turbo at all on this one. I was sure the turbo wasn't working until I did a few mean full throttle to 70 runs. If I didn't have a turbo I'd sure be making smoke in my mind, but it doesn't smoke. There is vacuum to the wastegate actuator at idle, the wastegate was solidly shut. It really isn't that gutless once your foot is in it, it's the light driving that it seems like it left it's sack somewhere.

Good to hear that just eliminating the EGR and getting rid of the kitty will make it breath better. I am still considering straight pipe for the muffler, but I might be loaning this one for trips, and that might not score me many points.

Yep gauges are in the works, after I take a lil trip down to DIS to pick em up.

Casey, what's your Tahoe geared? I'm thinking mine's 3.73 as it runs 2150 at 70 with cruise set. 265/75R16's I was hoping for 3.42's...

Gotta test the 4x4 out, it's push button, the rear in does have a limited slip though (tested that one out in the field next to the shop :D )

[arveetek]

Yep gauges are in the works, after I take a lil trip down to DIS to pick em up.

Casey, what's your Tahoe geared? I'm thinking mine's 3.73 as it runs 2150 at 70 with cruise set. 265/75R16's I was hoping for 3.42's...

Gotta test the 4x4 out, it's push button,

I just ordered a set of guages from Kennedy this evening....soon I'll be able to see what's really going on...

My Tahoe has 3.42's and 265/75R16's. I also have the manual-shift 241 transfer case.

Casey

[dieseldummy]

Damn John, that's a fun looking little rig! The question is how far will you take this one...? ;)

[john8662]

Damn John, that's a fun looking little rig! The question is how far will you take this one...? ;)

Oh, expect a nice "burnie" video in the near future...

It's fun to drive, still lots of little bugs to work out. Like... No Service Engine Soon light, guess someone "fixed" that, time to re-bulb and see what's up.

Casey,

I'm not completly sure the turbo is working either, absolutly no whistle, no nuthin.

Good you finally got some gauges on the way. I'm seriously thinking of taking the cash leftover in the pocket and heading over to DIS and getting a 3 gauge full pillar and some pointers to fill the holes. I can't stand not knowing what's going on, plus it's time to get rid of the "stock"...

[arveetek]

Casey,

I'm not completly sure the turbo is working either, absolutly no whistle, no nuthin.




Same here. I do get quite a bit of black smoke on full throttle, so that's why I suspect no boost.

Casey

[Warren96]

Mine has none either.The only time I heard the turbo is when i temporarly put a glasspack mufler on.I didn't like the way it sounded.I am back to my stock exhaust system.

[arveetek]

Casey, what's your Tahoe geared? I'm thinking mine's 3.73 as it runs 2150 at 70 with cruise set. 265/75R16's I was hoping for 3.42's...



John,

I paid attention to the tach on the way to work this morning, and I noticed that my rpm's are the same as yours....2150 at 70 mph with the same size tires. I bet you have 3.42's as well. The 265 tires on my Tahoe are oversize, supposed to have 245/75/R16. I'm sure the speedo hasn't been affected, so I'm actually traveling faster than indicated speed.

Casey

[JohnC]

Something's wrong...

With 3.42 gears, a 0.74 OD ratio and 265/75 tires you should be seeing 70 mph at about 1900 RPM.

With 3.73 gears it should be about 2050 RPM at 70.

[Robyn]

Nice truck
I have looked high and low for one of those and finally gave up and bought a cheap 94 4x Burb off ebay instead.
The thing had more codes than a batch of spies and was sitting under a tree covered with bird poop.

Took only a few hours to get the old girl up and flying though. new battery cables and a new vacuum line to the turbo ( the other one was gone completely from the solenoid back)
So now we have two here at the ranch, the one I just rebuilt and now another one and as a real perk they are the same color too.
Good luck with your new toy.
Looking forward to hearing about all the Mods.
Robyn

[john8662]

.75 OD ratio for the 4L80E actually.

Looked at the door sticker and it says to use 265/75R16's, So Casey, are you sure your door sticker says for 245's?

I'm only guessing on the actual RPM on my view point on the tach. I'd say it looks more like 2100 than 2050, remember the .75 ratio, that could account for the error too.

On other notes, still bug chasing on the little 'hoe, got a new set of glows, was starting on 4 good 11g's, guess that's what came in from Factory on '96. Had a reman starter sitting on the shelf to fix the slower cranking one that was on it, starts much better now, surprised it started well enough before.

Upgrades:

Heath ECM on the way :D

Going to cut the exhaust this week sometime and install that new mandrel downpipe and meow delete.

Gauges?

DIS didn't have one of my gauges in stock so I ordered one from USdieselparts along with the full pillar verses just the two gauge pod. I couldn't justify a trans temp gauge on this rig, since I won't be pulling that much with it.

So far, I'm having fun, I musta missed 6.5's far too much.

[JohnC]

.75 OD ratio for the 4L80E actually.

Picky, picky!

OK, 3.73, 70 mph, 2080 RPM
3.42, 70 mph, 1907 RPM

My '93 with 3.42 gears, NV4500 and stock 245/75 tires did 72 mph at 2000 RPM.

TMSAISTI!

(Quit puzzling over it and read the RPO codes out of the glovebox!)

[john8662]

GU6, right next to the G80 code, middle of sticker.

Explains the acceleration lacking, but doesn't explain the RPM, unless the pulley on the alternator is the wrong size, here we go again...

Maybe it's time to service the rear end and count some teeth. Those stickers are known to lie, especially when someone else has had the rig before you have.

I went around for years thinking my ol '86 had 3.08, because that's what the sticker in the glove box said. Did the service, counted ring and pinion teeth, found 3.73's and that the tranny mechanical speedo gears had been changed out to match (someone did it right)...

[arveetek]

I just checked my stickers again...yep, my Tahoe calls for 245/75R16's. I too have the GU6 axle....3.42's. I don't have the G80, though.

I seriously doubt the previous owner would have swapped front and rear gears on my Tahoe. I wouldn't be surprised if the alternator pulley is wrong though.

Casey

[JohnC]

Here's a link to a free program you can use to check your tach:
http://www.tunelab-world.com/rpmsound.html

Also, have you confirmed it's in OD and that the TCC is locking up?

[arveetek]

Also, have you confirmed that the TCC is locking up?

Yep, TC locks up fine above 50 mph.

Casey

[john8662]

It's my Tach!

Did the same run last night, level ground, tach showed 2k with the cruise mashed right on 70, hmm. Earlier in the day I noticed the tach jump a little, so I think it's not as accurate as it should be. Probably warnings of alternator troubles later, luckily I have a spare sitting on the shelf that'll plug right in, in that event.

So, we've got 3.42!

JohnC,

Thanks for the link to the software, I'd like to try that out sometime.

[Craig M]

Jack the axle up, turn the wheel and count the wheel rotations to produce one driveline rotation.