The 4.88 mega thread!!

Mine was about 1400 for the 4:88's with REM polish from SDHQ, and I had my buddy install them at his shop. I also purchased a case of the Lucas oil HD synthetic gear oil. Total price around 3000. I paid 1500 in labor. Might be a little high only cause I had him take care of some routine maintenance stuff while it was in there, new rear brakes, wheel alignment/balance and tire rotation. I can't believe how much of a difference the gears made tho.

 

I did a cost breakdown here ($2,270)

 

Was it 85w-140 Lucas? It’s recommended to not use synthetic with new gears. The 85w-140 only comes in non-syn from Lucas

 

Getting ready to order Nitro 4.88s for my 2020, and was planning to REM polish, though during an email conversation with a very reputable distributor was told that Nitro Gears are tripled polished and REM polishing voids the manufacturer’s warranty.

I’ve ready through most of this thread, though not all, and haven’t seen this yet in the discussion. Thoughts?

 

It's been brought up in the 5.29 thread, don't worry. There's no way they can find out unless they spend money

 

What? Whatever “triple polished” means. They looked like stock gears before REM. After REM they are way smoother and shiny

Without REM


With REM (notice the beveled corners on the teeth)

 

Don't know who your "reputable" distributor was (Slee or RSG ?). I got mine directly from Nitro. They looked smooth and dark - like they should unless they have been REM'd. If they polish them it is only to remove rough surfaces and other surface blemishes. As for REM voiding the warranty - I'd call Nitro and ask them. Good chance your won't be working with your "reputable" distributor after that call. All REM does is use a micro cleaning/polishing process so the normal break-in process can be avoided. They do look nice though … all bright and shinny! Just like @SpeySquatch has provided a pic of.

 

FWIW, I was speaking with the fine folks at Just Differentials. So, the “rough” coating is black phosphate after the polish. The initial 500 miles rubs the phosphate off the mesh but the rest of the gear set stays coated inhibiting corrosion. They do not recommend polishing, though acknowledge it’s all the rage on the internets at the moment.

That said, 4.88s are ordered and I’m looking forward to getting them installed.

 

Steven at ECGS straight-up talked me out of REM polishing.

 

They may be able to spot REM because it’s very shiny but you could probably just claim ignorance. Cryo treating is more complicated and requires lab testing.

 

Most of you know this, but come Dec I am going 5.29 in my 2019 MT.

AM I nuts?

Didn't get a ton of grief in the 5.29 thread so I came here for some abuse.

 

Just wondering, has anybody put manual gears in the auto diffs? It’s a little under half the benefit of 4.88s. Might be able to get them out of a yard reasonably cheap?

 

One guy did @Rus$. He wished he went bigger (as I recall) because on paper there is almost no gain. Even with 4.88’s there’s only like an avg 400 rpm gain per gear at cruising speed

 

4.88s should provide right at 25% increase in rpm for the same speed/gear. 4.30s around 10%. I pretty much had my head set on one of the new superchargers to add to the cost of a travel trailer in the next 2 years. But am thinking this might be a route to save about 2/3rds.

 

I don’t think those #’s are accurate given 5th and 6th are overdrive gears. Also don’t forget tire size changes RPM ratios.

Maybe this will help in your decision (disclaimer: not my handywork)

 

4.30s were a perfect match with the 33s as far as stock ratio went. Would of ran awesome if I’d had a super charger or turbo. Swapped to 5.29s before I sold it and it still wasn’t exactly right imo.

 

Yep, did the math in the tables. Final drive ratios are simply modified by 4.88/3.91, or 1.25. That’s a nice table for sorting out options.

 

Well, I just finished reading this entire thread over the course of a week or so. After reading this I’d say the 4.88 gear swap is probably the best mod for drivability of the third gen. I haven’t done it yet but I’m convinced I need it now. My issue is towing. I tow a 18’ camp trailer and it sounds like this would help quite a bit with towing. However, I’m still on stock tires as they haven’t worn out yet. I’m planning on going up to 265/70R17’s in about 10k miles. Anybody tow a lot with 4.88’s? If so, how’s your experience over stock gears regarding towing?

 

4:88's OVtuned, I pull all day in 4th and 3k rpms about 60mph. My 16ft hybrid trailer weigh around 4k. I get around 8-12 mpg, I won't tow in an overdrive gear, rather pay for gas than a new transmission. I hated it stock while towing!!!!

I would strongly recommend a scangauge II or equivalent to monitor transmission temps. Also I have found pinning the thermostat on the transmission helps a bunch.

 

[QUOTE="awdvkd115, post: 21992106, member: 215429Also I have found pinning the thermostat on the transmission helps a bunch.[/QUOTE]
Can you explain this to me? I’ve never heard of that before???