What happens when all of the real craftsmen disappear from the auto repair business? Sean has gone above and beyond again. My 62-year-old Ford 9-inch rear end probably hadn't been opened in decades, if not never. Sean found a bad pinion seal, bad axle seals, some bad bearings and a lot of other stuff like water and rust that needed attention. The only symptom was that the pinion seal leaked. At the end of the job as I was picking the car up, Sean mentioned that the rear brake shoes had been installed improperly. Sure enough, when I got into it today, a previous mechanic (who shall remain nameless) put both primary shoes on one side and both secondary shoes on the other. It's an easy fix, but, as I said at first, the real craftsmen are increasingly hard to find in the repair business. As usual Sean's pricing was reasonable and he did just what he said he would do in a timely manner. Five stars plus!! read more

Experienced guy, quality good work, and got my differential done quick. Highly recommend going here read more

River City Differentials - Auto Repair Near Me - Rancho Cordova, California

Yes I recommend Sean. Great guy honest work. Hard to find good shops these days. Far drive for me but would do it again. He knows his stuff.

They rebuilt the rear end for my 81 Cadillac Fleetwood and I am beyond happy. These guys do amazing work. read more

River City Differentials - Rebuilt rear end - Auto Repair Near Me - Rancho Cordova, California

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Gears/service Brought my jeep into re gear has been great Years later brought it for service Sean's a good guy knows his stuff and is fair Derek can figure anything out and just about build anything read more

Sean is the best out there. My truck lost the differential in Tahoe during a storm as soon as I was able to get it towed off the hill. He was able to take a look at it right a way he gave me the quote I thought it would take a few days. He then got a hold of me at 6 o'clock the same day and said the truck was done and I could come get it the next day. highly recommended best shop around fair price and a really nice guy. I would recommend having your vehicle towed from 2000 miles away to have him fix it. Thanks for everything. I appreciate your help Sean. AAA+ read more

Had my 80 series land cruiser differential gears done here and they did fast and great work! The 5.29s are perfectly setup and functioning. read more

River City Differentials - Auto Repair Near Me - Rancho Cordova, California

Yes if you're reading this that means u need rear end work yes this is definitely the place to go took my car to a shop and they was looking for a rear end for my Tahoe and was like it's hard to find one anywhere after a hour went by I found these guys called and talk to Sean one of the most simplest conversation gave me the cheapest price first or it could be price they both sounded good car is fixed and I couldn't be more happy big recommendations read more

My rear differential was going out for the second time after Folsom Lake Dodge "rebuilt it" and River City was able to get me in and do both differentials. I went wit 4:56 gears and a True Trac in the rear. They did a great job and were very easy to work with! read more

River City Differentials - They also repainted my cover while they were at it. - Auto Repair Near Me - Rancho Cordova, California

Gears can be tricky... Came here like a blind date! Didn't know what to expect not much out there about this place. I called talked to Sean made a appointment. And the rest is history my jeep & toyota both re-geared and no issues. read more

Had my first diff rebuilt here. Guy answered a ton of questions over the phone and gave me a quote. I was able to drop it off the same day, early afternoon, and got the call it was ready the next afternoon. Price was good, service was good. I was referred to this place by an acquaintance who drag races. read more

I had a bunch of noise coming from the rearend of my 08 ram 1500. I use my truck for work. They had me back on the road in 1 day. Man I was totally thankful for them. And I didn't have to break the bank. Thanks a bunch. read more

I dropped my truck off to have my gears changed. Truck had zero issues when i dropped it off. When i picked the truck up, everything looked good, but when i got home, there was oil leaking everywhere from my transfer case. When I called the shop to tell them, he said that there was no way he could've caused the leak, because he didn't touch the transfer case. That cant be true, because you need to remove the driveline to change the gears and he pinched the gasket in the transfer case, causing the leak. He told me that it would be my responsibility to take it all the way back to the shop and he wouldn't be responsible for fixing the leak. Ridiculous. I took it to a local shop who confirmed what i thought and showed me the pinched ring. I haven't had any problems with the gears he put in, but he really lacks in customer service and integrity. read more

I have been here twice with 2 different cars and both times they did a great job. They also had the best price and gave me a detailed list of all the costs. read more

Its been several years since he did the rear differential on my one ton work van. Its been trouble free. Seans my "go to guy" for my friend Wade that recommended him to me and myself. read more

Come here if you want your axles half assed and like to be cussed out when they don't want to admit they are wrong. When they make a mistake they blame the customer and act like dicks. They are just assholes and you should find another shop that's actually reliable enough to where u can drive home and not have your rest diff start smoking 3 minutes after leaving the shop (past experience) read more

these guys did an amazing job. i had them swap in eaton lockers for my 8" toyota front and rear diffs. dropped it off on a sat and they were ready the next weekend for pickup. i'm very happy that the gears had a good pattern and i have had no issues so far. the lockers for sure lock. i'm very happy. i will be coming back for future gear setups. read more

Took my GT500 here last year to get my differential rebuilt after abusing it road racing. He packed the sh*t out of my posi, and the car has been awesome on the track ever since. I decided to do a full-on upgrade this year: ditch the c-clips, welded 9" housing ends, 33 spline axles, racing studs, torsen LSD, and a full rear end suspension - watts link, torque arm, LCAs. And all this had to play nice with an AP racing rear brake kit, the one with the GM-style e-brake integrated with the caliper mounting bracket. Well, they didn't play well together. Of all the multitude of things that could be wrong, Sean and his colleague were able to sort out all the issues and narrow down and fix the problems. It's all custom work back there now, and the car is now rock solid, better than new. I included these details because walking into his shop most of his clients' rigs and most of the reviews here are for 4x4 / offroad / rockcrawling type applications (what else would you expect a diff guy to be working on?). But Sean is just as much a master at dealing with road racing and drag applications. If you need something special or custom, or you just need it done right, he's your guy. He is superb at what he does, and a friendly guy to boot. read more

They fixed my truck. Fair price, honest work, runs great. I would recommend them to friends and family. Get a quote somewhere else, then come here. You'll be happy with their work. Sean the owner, knows what he's doing, and has plenty of projects laying around. Nice equipment, plenty of parking. Safe area. read more

Sean is a standup guy. Do yourself a favor and bring your work to him. He repaired my F250 diesel rear diff in one day.

Did a great job. Just 3 days, and came in under what we thought it would cost. Will use him again.

Brought my '00 jeep wrangler in to get the rear end rebuilt... Sean is the absolute best!! I look forward to having him do more work/ upgrades on my rig.. thx Sean! !! I'll definitely be recommending you and your shop to everyone! !! Christy read more

The pinion seal on the rear differential of my jeep liberty was leaking so I brought it to river city differential on the advice of red rocket auto. He diagnosed the problem and fixed it up in less than 45 minutes. Rather than replacing every single part (which would have been upwards of 300$), he polished everything up and replaced the seal only. All this cost only 60$! He said this usually works about 50 percent of the time and that if I noticed a leak, he would credit me this amount and put it towards the full job. In all he is clearly a knowledgeable, friendly and honest mechanic who will do the repairs that are needed in a timely fashion. read more

Sean is one of the best business owners I've dealt with. Always on time and was more than helpful. So far Hes changed the gears in 1 Toyota 3rd member and put a locker in another at a very reasonable price and they work great. I recommend him to whoever asks me about differential work. I am currently working on a wagoneer axle Dana 44 swap into a Tacoma and I'm gonna have him put 5.38 gears in it for me because I'm confident in his work. Thanks again read more

3 months after my repair here is how I feel. You know back in the day in school there was always the guy you went to when your car needed help. Well this is your guy today. When it comes to drivelines, differentials rear ends, front ends and more this is my go to place. My Toyota Tacoma had 145,500 miles on the clock when I started to feel a little play in the front end. It got to the point where to the point that I was checking the front bearings every 2 -3 weeks (grabbing the top of the tire and pushing and pulling back and forth to see of there is any play or noise or popping feel), but it seemed tight. But I bought a set of front wheel bearings and seals to have them replaced. I shopped around my local area and they ALL wanted 6 hours to do it. Now this told me a couple of things, either they didn't know what they were doing and planning on learning at my expense or their business model was to over price their service and live off the uninformed. I called River City Differentials with 165K on the clock because I noticed a loping feeling on very sharp turns in a parking lot a couple of times. (Usually this is indicative of a front axle CV binding up and releasing, sort of a little surging effect). I asked him about how much to rebuilt my front axles. His honest answer was I could buy them cheaper online, and just bring them in and he would install them. Well as I had the bearings and seals and he would have already done most of the work by removing the axles I asked how much more to replace the bearings and seals. His answer was only $100 more. I ordered the parts. I took the rig in when the parts arrived and he was done with it in a little over 2.5 hours (what it should have been in the first place if the other guys knew what they were doing) and he came in on budget and on time. When I picked up it was like I'm driving it off the lot for the first time. The front end was solid and tight, and after 3 months it's still like new. He's a good guy, do yourself a favor and give him a call. read more

Took my Cobra to his shop in the morning and he did everything to my car in the differential from rings to gears to the axle shafts to the whole differential itself all for $300 and then when he said I needed an axle shaft he had one in the shop and oy charged me $100 for it so $400 total with my provided parts. Great guy and got the car back the same day ! Way better than any other shop that charged per thing I wanted done. read more

If you have an issue with your differential or want an upgrade, they are the guys to talk to. I've been taking my vehicles there for the last 10 years. read more

Sean was great, got my truck back on the road quickly, other shops wanted weeks. The cost was cheaper than other shops and felt he was super honest about what needed to be done without going overboard. Rear differential feels great. Thanks read more

I am a fair weather mechanic and do all my own work but don't have a press of special tools to do diff work. My pinion bearings were making noise on my 2000 4runner with 260,000 miles on it. Took it to a few places and they wanted to change the whole pumpkin out for 1000$. I called Sean and told him what I needed and he did it all for half that price and did a great job. Don't be fooled by the outside appearance of this shop it is one if the best in the Sacramento area for differential rebuilds and repairs. I chatted with Sean for a bit on other differential stuff and this guy really knows his stuff! read more

Took my 2013 mustang GT to get the gears changed. It was done on time and at a reasonable price. Car runs like a champ. I would recommend him to anybody. Thanks for the service! read more

Place sucks. A friend who used him in the past refered me because I needed my rear end rebuilt. Everytime I talk to the guy he acted like he had no time to talk and ask me to call back days or a week later. When I'd call back he was obviously annoyed to speak. Finally got truck done. A few monthes later the work he did developed a leak. Called back, he's annoyed at hello, tell him my issue and it was the same- call back next week. Call him back, tells me to call back a few days later. Finally paid another shop to fix his work. It took them an hour. Lost my business forever, and anyone else I know needing diff work. read more

Sean was helpful, accomodating, and friendly. The price to install my provided ARB air lockers and re-gear my 2015 Wrangler was very reasonable and better than 4 other area specialist shops. He even sourced some parts I needed, but didn't provide. The work was done well, clean, and fast. Picked it up on day two. Tested the lockers yesterday and they're working great. Bottom line, use this shop! Thanks Sean. read more

Sean is the man! I heard of him via word of mouth from some autocross friends. My GT500 had a habit of smoking the unloaded tire in tight turns under heavy acceleration while autocrossing. Occasionally this would trigger the computer to register a failure in the traction system even with all nanny systems disabled. Sean knows the Ford 8.8" rear end well and turns out they're purposely loose from the factory (which is fine unless you track your car!) For a very reasonable two hours fee, Sean tightened up the traction - lock system by increasing the count of friction discs and decreasing the count of steel discs. (This is my layman's description - he had a better technical description ) I could immediately feel the difference even in regular driving, and it felt more predictable and tight as I got more aggressive in the corners. Don't waste your time and money anywhere else - this is THE expert. Seriously! read more

Sean is a pro's pro and he did a fantastic job on my 97 4runner axle bearing. I didn't notice it at the time I picked it up, but he replaced some of the parts I forgot to source and you can just tell that he cares about his work. Definitely a craftsman at his trade and on top of it all he was about a 1/3 of the price that most of these other shops quoted. You can tell, based on the rigs laying around the shop, that Sean's knowledge comes from testing and first hand experience. I can count the number of times on one hand that I've needed a rear-end shop, but after dealing with Sean I wish I had more work for him.... yes that's how much I liked the guy. Maybe I'll go break a few more axles with confidence knowing that Sean is waiting in the pits. read more

I called around and asked questions, got prices for a rearend built at a few places and Sean was 30 to 40 percent less for the parts and labor than his competitors. But even more important he knew his stuff and has a good attitude and very helpful with answering all questions about my project. Don't let the unassuming small business front and the one man show put you off, This guy knows what he is doing and stands by his work with anything differential. I only wished he would do all types of auto service. I would straight leave my car there and know I'm getting a great service and an awesome price. read more

Sean sure doesnt seem like a morning person, but who cares. Who else do you know that can regear a 8.8 rear end on a 2014 mustang in 2 1/2 HOURS?! Seriously? Hes a super friendly dude i think after he gets a bit of coffee in him haha. My mustang is literally a well oiled mmmooonnnssttteerrrr now. Thanks sean!! read more