1997 GMC Sierra 3500 4x4 SLE 6.5 V8 TD

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

DarioGMC

Newbie
Joined
Jul 19, 2020
Messages
42
Reaction score
78
Location
Italy , north east, Veneto region
Hi everybody!!! I didn't write for a while but we're still working on the truck, so now it's time to write an update.
In July we made a big order on Rockauto, 1700 euros for something like 45 parts...everything for the manual conversion + everything for the complete front end rebuild + a set of KYB Monomax for 1-3" lift. We bought the NV4500 4wd mainshaft and 5th gear nut from Allstate gear.
I can say we've been satisfied with every seller.
So the first thing we did is the 2wd to 4wd conversion on the NV4500, to be honest, i thought it would have been a more difficult job...but. at the end of the day, we've been able to do it without any problem and just in few hours.
My brother also had an "art attack" and invented a solution for the famous 5th gear problem i'll show you in the pics.

You must be registered for see images attach


You must be registered for see images attach


You must be registered for see images attach


You must be registered for see images attach


You must be registered for see images attach


As you probably know, between the 5th gear and the 5th gear nut there's a vibration dampener or a spacer, so my brother designed this special spacer. The idea is the following :

there's a high wall tube outside and inside another tube splitted in two halfs. As you can see from the pics it has a profile that matches the shaft profile just to stay in place the best way possible. If the 5th gear happen to slip back it pushes on the splitted tube that tries to open but it pushes against the big thick tube so it can't go anywhere (or at least this is the idea).
I realise my explaination is a bit ******.....i tried to do my best...if i could write about it in Italian it would be ways easier.

Then we also spent a ton of hours on the fron end, we replaced everything and restored the front part of the frame and all the control arms.
We also tried to make two new torsion bar keys because the truck is lifted (in a crappy way by the previous owner) but there was too much tension so we went back to the stock ones tried to crank not too much. We also made a couple of spacers for the upper ball joints so now we have a good working angle. We are very happy for the result, the truck is leveled and finally it has shocks with the correct lenght. Unfortunally at the moment i can't find the pics.

At the moment we are at a very important stage : we have to uninstall the transmission from the truck. We started yesterday with the transfer case....we thought removing the gearbox crossmember was enough.....but after a lot of cussing we discovered we had to remove the other one, the one where there are the torsion bar keys. So next week i hope we are able to remove everything.
For this post i think it's enough. See you for the next update!!!


And i want to say thank you to a lot of people here because i've found a lot of infos here and there for buying the right parts!!
 

DarioGMC

Newbie
Joined
Jul 19, 2020
Messages
42
Reaction score
78
Location
Italy , north east, Veneto region
A lot of work has been done, but finally we've got it!!!
The manual conversion is almost 100% completed. We did the first road test on wednesday and pratically everything was ok at first attempt.
Only the clutch pedal had a little too less travel and reverse gear wasn't very happy to engage...this was caused by a spacer we made between the master cylinder and the firewall because the clutch pedal wasn't perfectly aligned with the other ones. But the we made a thinner one and now it works as it should.
This because we haven't been able to find a clutch pedal bracket, so we bought a brand new clutch pedal on ebay and we made our own bracket....not the easiest job but we did it.
Another part we had to make is that "frame" (or maybe bezel? i don't know how to call it in English, sorry) that goes between the floor , the carpet and the gear lever boot. We made it in plastic with the cnc milling machine.
The last step has been the drive shafts.....we lost a month with a stupid guy from Rome who has a '96 Suburban for parts....at least he said he sold parts but, at the end, he was just a time waster. So, after some research we find a superb mechanic specialized in American cars just at 30km from us who modified the front shaft and made a brand new rear shaft (the slip yoke is the only reused part), and every u joint is new.

.....and finally on the road!!! What can i say? It worths every hour spent on it. It's an absolute pleasure to drive this truck with manual transmission. It seems it has twice the power...the clutch is a bit heavy but absolutely not a problem. I like how the NV4500 works, the shifts are smooth, i tried the very short 1st gear just for curiosity....if you are not fully loaded or if you don't have to start from a very steep road you don't need it. Of course it's a truck's transmission, don't expect to shift like on a BMW.....but it's the way it should be. My YJ 4.0 was more or less the same.
I also discover that the rear lsd works fine, we did some "drift" on a roundabout......the worn out 4l80e didn't allow you to do it.

We did twice the wheel alignment, now we are almost ok. I reached 120 km/h ( you prefer to say 75 mph, i know) and zero vibrations. But, i don't know why, when you go straight the steering wheel isn't perfectly centered....maybe we have to do it another time?

The truck is absolutely drivable, but we still have to do a couple of things :

_ set the cruise control switches the correct way

_ bring the truck to the guy who modified the shafts to let him set the ECU to manual transmission, so the engine light will go away.


.......and then, of course, we'll have to start the bodywork.


I made a little video but i don't know how to post it.
Next days i'll do some pics.
 
Last edited:

DarioGMC

Newbie
Joined
Jul 19, 2020
Messages
42
Reaction score
78
Location
Italy , north east, Veneto region
Hi everybody, as said i post some pics :

an interior view, it's not super clean....but it's a "work in progress vehicle" at the moment;)

You must be registered for see images attach


Here you can see our home made clutch pedal bracket.

You must be registered for see images attach


In this second pic you can notice the bronze bushings we made, we also put a steel shaft (or pin? i don't know the correct word) so we didn't trust so much into the plastic bushings the pedal came with.

You must be registered for see images attach


Here a view of the gearbox and the repaired and repainted crossover pipe

You must be registered for see images attach


In this you can notice that after the oil pan gasket and rear crank seal replacement everything is clean

You must be registered for see images attach


Here you can notice another part we had to make our own : the flywheel dust cover. We made it from aluminium sheet metal with the grinder and with the cnc milling machine.

You must be registered for see images attach
foto su web

Brand new rear drive shaft and shocks

You must be registered for see images attach


Brand new Rancho steering stabilizer. .....you can also notice my '78 Guzzi V50 and my brother's '95 Honda CR 250 R covered of dust, it would be great to have the time to ride...

You must be registered for see images attach


That's all for now.
 
Top