Most transmission rebuilds fail because the rebuilder cut corners, not because the rebuild was hard. Here are 10 questions that separate good shops from bad ones.
Shop rebuild kits and parts by transmission
Why this matters
Bad rebuild = repeat job:
- Comeback in 5,000-30,000 miles
- Often outside warranty
- Total cost = 2x first rebuild
Good rebuild lasts:
- 100,000+ miles
- Restores like new feel
- Often outlasts truck
Question 1: Do you replace the torque converter?
Right answer:
- Yes - always, with rebuild
- Old converter carries clutch debris
- Will recontaminate new fluid
Wrong answer:
- Only if it tests bad
- Customer choice (corner-cutting)
Question 2: What clutch material do you use?
Right answer:
- Raybestos GPZ (specific brand)
- Alto Red Eagle
- Borg Warner OEM
Wrong answer:
- Whatever the kit comes with
- Generic / no-name brand
- I do not know
Question 3: Do you replace bushings?
Right answer:
- Every bushing inspected
- Worn ones replaced
- Or full bushing kit installed
Wrong answer:
- Only if they look bad
- Not normally
Question 4: Do you upgrade the sun shell? (4L60E specific)
Right answer:
- Beast sun shell standard
- Sonnax HD shell
- Even on stock trucks
Wrong answer:
- Stock is fine
- Only for HD applications
Question 5: How do you adjust clutch clearance?
Right answer:
- Feeler gauges
- Multiple clutch packs tested
- Within spec exactly
Wrong answer:
- Stack everything and hope
- Set it and forget it
Question 6: Do you pressure test before delivery?
Right answer:
- Yes - line pressure verified
- Each clutch air-tested
- Test results documented
Wrong answer:
- Sometimes
- Only if something seems off
Question 7: What warranty do you offer?
Acceptable answers:
- 12 months / 12,000 miles minimum
- 24 months / 24,000 miles good
- 3 years / 50,000 miles excellent
Red flags:
- 30 days only
- No warranty
- Parts only, no labor
Question 8: Do you scan and update PCM after install?
Right answer:
- Yes - check for software updates
- Clear adapt values
- Test drive to relearn
Wrong answer:
- Why would I do that
- Customer can drive it home
Question 9: Can I see the old parts?
Right answer:
Wrong answer:
Question 10: Do you flush the cooler lines and trans cooler?
Right answer:
Wrong answer:
Bonus questions for HD builds
For tuned / towing:
- Triple disc converter included?
- HD frictions standard?
- HD shift kit installed?
- External cooler upgrade offered?
Other green flags
Look for:
- ATSG certification
- BBB rating
- Specialty in your trans family
- Builder you can talk to (not just service writer)
- Clean shop (organized = careful)
ATRA membership:
- National rebuilder warranty
- Honored at any ATRA shop
- Useful if you move or travel
Red flags to walk away from
Too cheap:
- Rebuild for $800 (impossible)
- Cutting somewhere
- Will fail fast
No diagnosis fee:
Cannot answer technical questions:
No core charge / no return policy:
Price expectations by transmission
4L60E:
- Standard: $1500-$2500
- HD: $3500-$5500
- Below $1200 = cutting corners
4L80E:
- Standard: $1700-$2700
- HD: $3500-$6000
Allison 1000:
- Standard: $3500-$5500
- HD: $5500-$8500
47RE/48RE:
- Standard: $2500-$3800
- HD: $4500-$8000
Bottom line
Spend 30 minutes asking questions:
- Saves $3000+ in repeat rebuilds
- Filters bad shops fast
- Identifies builders worth using
Get 3 quotes minimum:
- Compare answers, not just prices
- Cheapest rarely wins
- Middle quote usually right
Need rebuild kits, HD parts, or complete bundles for DIY? Visit our main catalog. Every major US transmission family. Free shipping over $70.
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