Any guys towing with a 1500 5 speed anymore?

[Blue Turd]

I regularly tow 5-6k with my truck. It’s a 5.0 TBI with NV3500 and I believe 3.42 gears. All original with 260k on them all. Truck is happy with it if you keep the revs above 2k. Highway driving is in 4th gear. No faster than about 65.

Mind you these heavier trailers have brakes(surge). They also aren’t big campers with lots of wind resistance. I do also tow around my utility trailer and flat tow cars in the 2-4K range with no extra brakes. Still drives fine, just be aware of the extra braking distance of course.

I love towing with the manual. So much better control, especially down long grades. So sad manual trucks barely exist anymore in this day and age.

 

[Spookers]

I'm assuming I cant just insert 5 lug axle shafts. Wheel change is mandatory I take it?

Not necessarily. I've taken 6bolt axles and carefully welded shut the existing holes and drilled the 5bolt pattern. If you do this you need to get or make a special drill bit that measures .600", I used a 5/8 bit and ground it down. You will need a way of indexing so your bolt pattern is dead on. machine shop can re-drill a new bolt pattern if you can't.

 

[Spookers]

Also when doing this I used 06 gm 2500hd 6.0 studs off rockauto as they have a pilot and about 1/4" more threads which I recommend for a few reasons, first its good to use new hardware, second more thread engagement especially for aluminum rim's, third the pilot helps a lot with spinning on lug nuts

 

[5speed91]

That Caprice Wagon has peaked my interest! Sounds like a really cool car.

 

[5speed91]

Glad to know you have been towing with your 5.0L NV3500 set up for a while. I agree about the driver being the wildcard here. GM rates these trucks with the same towing capacity regardless of manual or automatic, however they do specifically spell out that they recommend the automatic for towing. I think this is the for same reasons as stated above.

Check your RPO label in the glovebox. GU6 for 3.42 or GU4 for 3.08. I was very surprised mine had 3.08s as I had never seen that ratio in a GMT 400 prior to. Mine also originally started life as a 305 truck.

 

[Supercharged111]

Glad to know you have been towing with your 5.0L NV3500 set up for a while. I agree about the driver being the wildcard here. GM rates these trucks with the same towing capacity regardless of manual or automatic, however they do specifically spell out that they recommend the automatic for towing. I think this is the for same reasons as stated above.

Check your RPO label in the glovebox. GU6 for 3.42 or GU4 for 3.08. I was very surprised mine had 3.08s as I had never seen that ratio in a GMT 400 prior to. Mine also originally started life as a 305 truck.

My owner's manual specifies a lower rating is for manual vs automatic. Has anyone ever destroyed an NV3500? Worn out syncros are not what I'm asking about.

 

[5speed91]

My owner's manual specifies a lower rating is for manual vs automatic. Has anyone ever destroyed an NV3500? Worn out syncros are not what I'm asking about.

Are you talking about your 1998? I always wondered about this. 1991 Sales brochure lists no difference in max trailer weight with either transmission but still have a disclaimer recommending the auto for any towing applications. However, I have also noticed that most things I have read on the NV3500 list its torque capacity at 300 ft/lbs. I always wondered how/why if that was the case, they continued to offer this transmission behind the 5.7L vortec with the 330 ft./lbs rating. I also wondered if this is related to why there seem to be so fuw vortec 5.7 trucks with this trans compared to the 88-95 models. Maybe they changed tow ratings to discourage people from opting for the manual. I'm sure they had a lot of warranty claims over the years in manual trucks especially for those who could not drive one very well.

 

[gearheadE30]

That Caprice Wagon has peaked my interest! Sounds like a really cool car.

It is, but rust has basically killed it unfortunately. Random video here:

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Check your RPO label in the glovebox. GU6 for 3.42 or GU4 for 3.08. I was very surprised mine had 3.08s as I had never seen that ratio in a GMT 400 prior to. Mine also originally started life as a 305 truck.

My '89 C1500 RCLB was a 350, 5 speed, with the 3.08. Not sure how common it is, but there were at least a few out there.

My owner's manual specifies a lower rating is for manual vs automatic. Has anyone ever destroyed an NV3500? Worn out syncros are not what I'm asking about.

The only NV3500s I've actually seen completely killed were from low or incorrect fluid. You HAVE TO use synchromesh fluid in these, and if it is even a little low, it will starve the intermediate shaft bearings of oil.

 

[Blue Turd]

I use the Amsoil Synchromesh fluid. Expensive but worth it (especially for how infrequent changes are). Shifts are smooth and easy even when freezing cold.

My truck also has a Hurst/Core shifter installed. Makes shifting way more fun and “sporty” than the sloppy stock shifter. It also cured the sometimes hard 2-3 shifts these trucks have. Not to mention it looks really cool [emoji41].

 

[5speed91]

I didn't expect that wagon to be boxy!!!! That's awesome. My first car was an 88 Caprice and my second was an 89. I love those things!

Ill have to check out the amsoil fluid. Mine seems to behave the opposite. Shifts great first 5-10 miles of operation and graduately the pedal gets noticeably (but not terrible) more stiff and the shifts are less smooth. Sometimes I can even here a creaking noise under the truck when I depress the pedal or release after several miles of operation. I think its a hydraulic issue however the whole clutch and hydraulics are new except for the master cylinder.