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-   -   Anyone run 4.88's and 285/295's on their 80? (http://www.risingsun4x4club.org/forum2/showthread.php?t=20623)

coax 12-18-2013 05:14 PM

Anyone run 4.88's and 285/295's on their 80?
Hi All,
Hoping to get some impressions and feedback from people who have run 285's or 295's on their 80 with 4.88 gears. I have been contemplating re-gearing for a while now but have yet to pull the trigger.

I spend probably 90% of my time driving at or below 65mph. During the winter nearly all the driving is at 8k+ feet in elevation with 285 snow tires. (I would plan on keeping the snow tires this size). Typically just up into the mountains to go skiing, etc. Most of that driving is <50mph, though if I head up I70 once in a blue moon speeds would be a bit higher(at least on the downhill).

During the spring/summer/fall its a mix of heading out to utah and exploring around CO for mountain biking, hiking, etc. Typically even with my stock gears I stay at about 65 on the highway.

I recently replaced my full exhaust system with a borla/magnaflow bolt in and did the O2 sensors at the same time. My hope was that all new equipment would give the 80 a little extra pep, but it actually did the opposite. I do realize that 80's are not fast, that the extra weight and slightly oversize tires don't help at all, but I struggle sometimes to hold second gear in many places.

I briefly considered going the SC + intercooler from Atoyot1031 on mud, but at a total cost of probably 4500 and possibly having to run high octane fuel during the summer makes it a less desirable option right now. Plus in the event I can put together a trip to south america being able to run on low grade gas would be really nice.

So, I am considering going with a 295 Hankook MT for the summer when I'd have more highway miles going to the desert, sticking with the 285's for the winter, and regearing to 4.88's. Seems like that might be a good option to help compensate for the altitude a bit?

If I did do this I'd sell my 285 terra grapplers, and depending on all the prices I think I'd be in at about 1800 net for tires and gears....which is a pretty big chuck of change.

Anyone run a similar setup and have an opinion one way or another? I don't mind driving slow on the highway but I'd rather stay long hauls in first gear when doing shorter drives up to go skiing.


Pictures just for fun:

The intercooler that is nice and pricey too!

My snow tires that I really like:

Hankooks that come in a 295

LARGEONE 12-18-2013 08:44 PM

Hi, Corey...I would like for someone who knows more than me to comment on whether it is OK to run the 80 w/ 4.88s and 33s for a long time (i.e. higher RPMs, etc).

I can comment on the additional "power" going up the passes. Just ask OilHammer and Chris Davis (can't keep track of his latest forum name!) about how well my 80 kept up going up the passes the last few times!!! Corsair can also comment about how "peppy" the 80 feels with this set-up. I have actually been running my 4.88s and 33s for some time now as I wait to wear out my set of 33's. I will likely try to go to 35s after this set of tires, but I'm not completely sure because I have really liked the way the 80 goes up the mountains now!!! Sometimes when it downshifts, though, I do fear my RPMs are too high...like well over 4K rpms! Anyway, feel free to ask any other questions...I've been running this set-up for a bit.

nakman 12-18-2013 09:51 PM

Farnham runs 4.88 and 295's Paul, and has reported positive results. He sees a lot of Vail Pass action.. also I know Convert ran 4.88's and 285's for some time as well, before switching to 35's. As you know RPM's get a little high on the wide open highway and may limit top speed a little bit, but for the other 95% of your driving it's nice to be a little peppier.

LARGEONE 12-19-2013 10:19 AM

Thanks, Nak...I've enjoyed the re-gear for the most part. High RPMs and slightly rougher shifts (may be my solenoids) are the only downsides I've noticed. I'm not really one to drive 80 MPH ever...not even in my cars that can do it. I think all of my years selling for Johnson & Johnson took the speeding out of me. There was always the threat of losing your job for speeding tickets, so I'm a fairly conservative driver now. This was a big change for me considering the Air Force almost kicked me out for having too many interactions with law enforcement over the way I drove!!!

farnhamstj 12-26-2013 08:10 PM

I really like the 4.88's and 295.75.r16 bfg set up. Greatest ever for pulling a pop-up over the mtn. passes. With the auto tranny, I can't say I can really tell the difference wheeling, but on the pavement for sure and money well spent. (98-99 100's come stock with 4.33 gearing) My truck comfortably drives at 80mph. Slows to 65 pulling camper up to 10,000ft.

I can only assume an 80 would benefit from the same upgrade.

Corbet 12-27-2013 10:20 AM

I never ran 33's with my 4.88's but the gear swap definitely was noticeable with my 315's. I can cruise along at 65 MPH and 2600 RPM on the interstate pretty easy depending on grade. Towing is way better. I rarely have to use 1st gear now on the hills:o Like you I don't see 65+MPH often. There is not an interstate for hours in any direction from down here.

The one thing to keep in mind though is after 3200PRM your MPG is going to drop considerably due to fuel management. So what ever speed that ends up being will kind of be your top end for cruising on the HWY without massive fuel consumption.

Wheeling in the rocks offers more control.

I still want the SC or a turbo.

Townsend 12-27-2013 11:50 AM

Excuse my ignorance guys, but what is the process/cost of regearing to the 4.88?

Corbet 12-27-2013 12:10 PM


Originally Posted by Townsend (Post 243931)
Excuse my ignorance guys, but what is the process/cost of regearing to the 4.88?

A lot. Parts for a locked 80 are over a grand. Then the labor. I delivered my 3rds to the shop and got out of there for around $500 in labor. If you simply dropped off your truck at a shop expect $2K+. Unlocked trucks are a little less as the set up kits are cheaper.

While its all torn down most will rebuilt the knuckles/hubs so there is that cost too. And well if your not locked there could be the price of a set of ARB's;)

Most people chose Nitro gear sets. Slee is a local supplier. I did my gears during a front housing repair: http://www.risingsun4x4club.org/foru...highlight=4.88

coax 12-27-2013 05:02 PM

Thanks a bunch for the feedback everyone! I'm glad to hear that no one feels that gearing down that low "ruined" the vehicle. I suppose if I really didn't like it I could always sell or trade the thirds for a stock set. I think for an initial upgrade this is a good way to go. I've got about 20k on the front and rear axle rebuilds so by the time I get around to it it will be close to the maintenance time for those anyway. It will be really nice to get out of the driveway without having to really get on the gas on a cold engine.

I'd plan on pulling the 3rds myself and then taking them somewhere to have the gears setup. I think i figured about 450 for the Nitro R&P's, then maybe 300-500 depending on if the "true" full master install kit is necessary or if the installer needs to replace the 2 smaller bearings.

What is the consensus on bearings? Are timken's acceptable or is it worth any extra to go with Koyos? Or maybe koyos's aren't' even available for some and there's no choice?

Thanks again everyone. :cheers:

Corbet 12-27-2013 06:07 PM

I used what ever bearing was in the master install kit form Carl:http://www.justdifferentials.com/MKT...mktlc-eloc.htm Why try to skimp on such a large service? Just put in the new parts and know you should never have to service it again.

Try out your winter tires before buying new summer rubber. If you think its geared a little low just buy 315's ;)

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