Recommendations sought from 5 speed owners

[5speed91]

So my truck has 249,000 on the original transmission. Pilot bearing or throwout bearing is noisy in neutral and amazingly the thing still shifts pretty good after all the miles. A little slow going from 1st to 2nd and almost impossible to downshift to 1st unless going under 5 mph but other wise working pretty good. The syncros are a little noisy at higher RPM shifting also from 1st to 2nd. I am also seeing microscopic brass looking particles in the oil last time I serviced it. As I mentioned in a previous thread, I obtained a 5.7L TBI engine from a 93 Caprice police car and would like to replace the engine and the trans at the same time.

With everyone saying how complicated these transmissions are I am not really inclined to go out and see if a local trans shop will rebuild it unless I have no other option.

I really want to know if any of you guys on this forum have bought a remanufactured light duty 5 speed from one of the few online sources where you can still buy one. I'm seeing them in a few places for around 800-900 bucks. If so did you have a good experience and would you recommend a particular retailer?

Since my truck should have the 5LM60 trans, is there any benefit to buying a NVG3500 instead of a replacement 5LM60? I know the 91s are supposed to be somewhat better than 88-90 trans but the only thing I can I can find that suggests the NVG3500 is better is that is has one shift rail instead of 4. Does that make it more durable or just easier to rebuild?

Also, are there different versions or improvements of the NVG3500 over the life of the GMT 400 platform? I know about S10 and Dodge applications but what confuses me is that everywhere says the trans is only rated for 300 ft lbs of torque when the L31 engine exceeds that, not to mention I'm still learning the various LS engines in the GMT 800 trucks that came with NVG 3500s. Not sure if 5.3 was an option with that trans but I have seen them behind 4.8s.

I have seen negative impressions here on the AC Delco clutch. What is good strong clutch (brand
?) for use with these 5 speeds in these trucks.

My truck is a 2WD, extended cab short bed with 31x10.50 tires and stock 3.08 gears. It has an LO3 now but will be swapped with an LO5 when the new tranny goes in.

 

[RichLo]

If I was in your situation, I would step up to a NV4500 for 1-ton trucks. I say that just because your already buying a new trans anyway, why not take a step up and know no matter what you do to your engine in the future, you wont ever hurt that trans.

 

[5speed91]

If I was in your situation, I would step up to a NV4500 for 1-ton trucks. I say that just because your already buying a new trans anyway, why not take a step up and know no matter what you do to your engine in the future, you wont ever hurt that trans.

That is a valid point and one that I continue to toss around. The problem as I see it is this, Unless I am mistaken, the 4500 trans is for all practical purposes a 4 speed trans for average driving. It would be awesome for towing but I don't do that very often. I feel like the heavier trans combined with the fact that that you don't use the low gear for normal driving would put it at a disadvantage from a performance point of view. If the 4500 is available without the low 1st gear than I stand corrected but as I see it, the 4500 with a low gear does not have much of a gearing advantage over a 4L60 (taking the low gear for towing out of the mix) where as the 5 speed 3500 has a gearing advantage with 4 full forward driving gears to row through before hitting overdrive. In other words, the ratios should be closer together on the 3500 than the 4500. I hope I explained that in a way that makes sense.

 

[sewlow]

GM based NV4500's up to '93 have a 6.34 1st gear.
From '94 on, they have a 5.61 1st gear.
'92 & '93's 1st gear is not synchronized.
Reverse is synchro'd after '96.
Ratios = 6.34 (pre '94) 5.61 ('94 & up), 3.44, 1.71, 1.00, 0.73. RPO=MT8
1 gallon fluid cap.

GM based NV3500 wide ratio gearing. 4.02, 2.32, 1.40, 1.00, 0.73. RPO=MG5. (Full size GM)
Close ratio = 3.49, 2.16, 1.40, 1.0, 0.73. RPO=M50 (S-series GM)
1.2 gallon cap.

• • 5LM60 units have a complicated arrangement of 4 shift rails. The NV3500 has one shift rail.
  • There are two designs for the 5LM60 input shaft and bearings (input shaft and main shaft). The first design 1988–1990 has a ball bearing with a roller bearing behind it. The second design has a much larger single ball bearing. The first design bearings are reputed to be failure prone. The updated input shaft and bearings carried through to the NV3500.

• These transmissions can be interchanged as a complete unit with the following deviations.
  • "Drop in" interchanges between GM S (S10 etc.) and C/K trucks will require modification of driveshaft length and crossmember placement. GM S models have a longer tail-shaft than C/K trucks.
  • Master & slave cylinder bore sizes went from standard to metric in 1992 (Master: 11/16"->18mm, Slave 13/16" ->20mm)
  • GM and Dodge transmissions (NV3500 & 4500) will not interchange.
    • The case and bellhousing are one piece with differing, engine specific, bellhousing bolt patterns.
    • Dodge uses Dodge specific input shaft length, spline count, and pilot diameter.
    • Dodge output spline count differs from the GM units.

The following all 'look like' they're same as an NV3500, but are very different internally.

• 1987 MG-290 MG= Muncie Gear
• 1988 HM-290 HM= Hydramatic Muncie
• 1989 5LM60 (early)
• 1991 NVG 5LM60 (late)

Check the glove box build sheet for the proper RPO codes when hunting the wreckers.

 

[5speed91]

My truck has the MG5 option. But as far as buying a reman one off the shelf, it looks like I put a NVG 3500 in no problem. I was just wondering if that would be considered an upgrade from the later design 5LM60. And which company has a good reputation here on the forum?